Full Opinion

****************************************************** The ‘‘officially released’’ date that appears near the beginning of each opinion is the date the opinion will be published in the Connecticut Law Journal or the date it was released as a slip opinion. The operative date for the beginning of all time periods for filing postopinion motions and petitions for certification is the ‘‘officially released’’ date appearing in the opinion. In no event will any such motions be accepted before the ‘‘officially released’’ date. All opinions are subject to modification and technical correction prior to official publication in the Connecti- cut Reports and Connecticut Appellate Reports. In the event of discrepancies between the electronic version of an opinion and the print version appearing in the Connecticut Law Journal and subsequently in the Con- necticut Reports or Connecticut Appellate Reports, the latest print version is to be considered authoritative. The syllabus and procedural history accompanying the opinion as it appears on the Commission on Official Legal Publications Electronic Bulletin Board Service and in the Connecticut Law Journal and bound volumes of official reports are copyrighted by the Secretary of the State, State of Connecticut, and may not be repro- duced and distributed without the express written per- mission of the Commission on Official Legal Publications, Judicial Branch, State of Connecticut. ****************************************************** PICTOMETRY INTERNATIONAL CORPORATION v. FREEDOM OF INFORMATION COMMISSION ET AL. (SC 18724) DEPARTMENT OF ENVIRONMENTAL PROTECTION v. FREEDOM OF INFORMATION COMMISSION ET AL. (SC 18725) Rogers, C. J., and Norcott, Palmer, Zarella, Eveleigh and Harper, Js.* Argued October 23, 2012—officially released January 29, 2013 Joseph P. Titterington, pro hac vice, with whom were Emily E. Campbell, pro hac vice, and, on the brief, Timothy P. Jensen and Amy E. Markim, for the appel- lant in Docket No. SC 18724 (plaintiff in the first case). Matthew I. Levine, assistant attorney general, with whom, on the brief, were George Jepsen, attorney gen- eral, and Kimberly Massicotte, assistant attorney gen- eral, for the appellant in Docket No. SC 18725 (plaintiff in the second case). Lisa Fein Siegel, commission counsel, with whom, on the brief, was Colleen M. Murphy, general counsel, for the appellee in Docket Nos. SC 18724 and SC 18725 (named defendant in both cases). Opinion ROGERS, C. J. The primary issue to be resolved in these appeals is whether public records that are pro- tected by federal copyright law fall within the ‘‘other- wise provided by any federal law’’ exemption to the Freedom of Information Act (act), General Statutes § 1- 200 et seq., set forth in General Statutes § 1-210 (a) (federal law exemption).1 The named plaintiff in the first case, Pictometry International Corporation (Pic- tometry), contracted with the department of informa- tion technology (DOIT) to license the plaintiff in the second case, the department of environmental protec- tion (DEP),2 to use certain computerized aerial photo- graphic images of sites within the state and associated data that are owned and copyrighted by Pictometry. The defendant Stephen Whitaker requested that the DEP provide him with, among other things, copies of the computerized images and associated data. The DEP responded that the images were not public records sub- ject to the act because, as copyrighted materials, they fell into the federal law exemption. The DEP indicated, however, that Whitaker could obtain copies of the pho- tographic images if he paid the $25 per image fee pro- vided for in the licensing agreement. The DEP also stated that the disclosure of the images to Whitaker would be subject to a determination by the department of public works (DPW) that disclosure would not pose a public safety risk pursuant to § 1-210 (b) (19).3 Whitaker then filed a complaint against the DEP with the named defendant, the freedom of information com- mission (commission). The commission concluded that, pursuant to the act, the DEP was required to provide Whitaker with copies of the photographic images ‘‘ ‘at its minimum cost,’ ’’ but was not required to provide the associated data. It further concluded that disclosure of the images without the associated data would not pose a public safety risk. Pictometry and the DEP then filed separate appeals from the commission’s decision in the trial court, which were subsequently consoli- dated.4 The trial court affirmed the commission’s deci- sion and rendered judgments dismissing the appeals, and these appeals followed.5 We conclude that, because the commission improperly ordered the DEP to provide copies of the images without first determining whether Whitaker wanted copies of the images stripped of the associated data, whether it was feasible for the DEP to provide such copies and whether doing so would pose a public safety risk, the matter must be remanded to the commission for further proceedings. We further conclude that, if the commission determines that Whi- taker wants and is entitled to copies of the photographic images, the copying of the photographic images must be done in compliance with the provisions of the licensing agreement and federal copyright law, including pay- ment by Whitaker of the $25 per image fee. The record reveals the following undisputed facts and procedural history. Pictometry is a private corpora- tion in the business of selling specialized aerial photo- graphic services throughout the United States. Pictometry’s processes are capable of capturing high- resolution oblique and orthographic aerial photo- graphic images.6 The images are owned by Pictometry and are protected by the federal Copyright Act, 17 U.S.C. § 101 et seq.7 Pictometry’s processes also generate metadata, or data that describes data, at the moment that a photographic image is taken. These metadata include the time that the image was captured, the angle at which it was captured and the latitude, longitude and altitude of the camera. The metadata is entered into Pictometry’s proprietary software, which is pro- tected by federal copyright and state trade secret laws. The software is capable of generating precise measure- ments of the photographed site. In March, 2006, Pictometry entered into a contract with the DOIT pursuant to which Pictometry granted the DOIT and other authorized state agencies, including the DEP, a license to use its software, metadata and images for governmental purposes (licensing agreement) in exchange for a fee of $793,000. The DOIT also agreed that licensed users would not reproduce any of the licensed images for use by persons not covered by the licensing agreement unless the licensed user paid Pictometry a fee of $25 per image, which fee the licensed user was authorized to pass on to the person requesting the copy.8 On July 5, 2007, Whitaker sent a freedom of informa- tion request by e-mail to the DEP, requesting copies of all contracts with Pictometry, all imagery provided to the DEP by Pictometry and any software required to view the Pictometry images. In response, the DEP sent an e-mail to Whitaker to which it attached a copy of the licensing agreement between the DOIT and Pictometry, except for appendix C to the agreement, which Pictome- try claimed was exempt trade secret information pursu- ant to § 1-210 (b) (5).9 The DEP stated in the e-mail that the requested images were exempt from disclosure under the act pursuant to the federal law exemption because they were protected by federal copyright law. The DEP also stated that Whitaker could obtain copies of the images if he paid the $25 per image fee provided for in the licensing agreement. Because the DEP had 139,148 oblique images and 245,806 orthographic images on file, however, it suggested that Whitaker might want to narrow his request to images of certain geographic areas. Finally, the DEP stated that no images would be released to Whitaker until the DPW had deter- mined that disclosure would not pose a safety risk. Whitaker then filed a complaint with the commission claiming that the DEP had violated the act by refusing to provide copies of the photographic images and meta- data. Pictometry filed a petition to intervene in the matter, which the commission granted. After Whitaker filed his complaint with the commis- sion, the DEP sent a letter to the DPW asking whether release of the Pictometry images would pose a signifi- cant safety risk to the public pursuant to § 1-210 (b) (19). The commissioner of public works responded to the letter on January 24, 2008, indicating that Pictome- try’s proprietary software would enable a person to manipulate an image ‘‘to include displaying a location from all four directions . . . and measuring the height, width and length of features such as buildings, bridges, roads, towers, trees and walls.’’ The commissioner of public works also stated that ‘‘the exemption of specific images itself may be a security risk. By redacting certain exempt images of important assets, we essentially pro- vide a road map to those assets.’’10 The commissioner of public works directed the DEP ‘‘to withhold from disclosure Pictometry’s software and [geographic infor- mation system] data of critical infrastructure and key resources that are not available to the public’’ because disclosure would present a risk of harm to the state and its citizens.11 The commission conducted a hearing on Whitaker’s complaint against the DEP on January 31, 2008. There- after, Whitaker filed a complaint against the DPW and a motion to consolidate the proceedings on that com- plaint with the pending proceeding against the DEP. The commission treated the complaint against the DPW as a motion to join the DPW as a respondent in the proceeding against the DEP, and granted the motion. Thereafter, the commission conducted additional hear- ings on the matter. Ultimately, the commission concluded that Pictome- try’s software and metadata were trade secrets within the meaning of § 1-210 (b) (5) (A) and, therefore, were exempt from the act. It also concluded that the Copy- right Act was not a ‘‘federal law’’ for purposes of the federal law exemption because copyright law does not require that copyrighted material be treated as confi- dential. In addition, the commission concluded that, because the DPW’s determination that disclosure of some of the images could pose a safety risk was based on the assumption that the metadata would also be disclosed, and because the images alone revealed noth- ing that could not be observed by visible inspection or a photograph of a site, disclosure of the images did not pose a safety risk for purposes of the exemption set forth in § 1-210 (b) (19). Finally, the commission con- cluded that ‘‘the charge of $25 per image in addition to the approximately $700,000 two year licensing agreement would be an unreasonable charge and [that the] DEP is not entitled to recoup those costs by charg- ing [Whitaker] for disclosure.’’ Accordingly, the com- mission concluded that the DEP had violated the act and ordered the DEP to provide Whitaker with copies of the images, without any associated metadata or soft- ware, at ‘‘its minimum cost.’’ Pictometry, the DEP and the DPW then filed separate appeals from the commission’s decision in the trial court, which appeals were ultimately consolidated for trial. The trial court concluded that the commission’s determination that the disclosure of the images to Whi- taker would not pose a safety risk was supported by the evidence; the commission had properly determined that federal copyright law is not encompassed by the federal law exemption because it does not shield copy- righted material from disclosure;12 and the commission properly determined that the DEP could not pass the $25 per image copying fee on to Whitaker because pub- lic agencies may not contract out of their obligations under the act. Accordingly, the trial court dismissed the appeals. Pictometry and the DEP then filed these appeals. Pictometry claims that the commission improperly determined that the Copyright Act is not a ‘‘federal law’’ for purposes of the federal law exemption. The DEP also makes this claim, and further contends that the commission improperly reconfigured Whitaker’s request to apply only to the photographic images, stripped of the associated metadata, without providing an opportunity for the DEP and Pictometry to respond to the request as reconfigured or to determine whether the release of the images stripped of the metadata would pose a safety risk. The commission disputes these claims, and also contends that the DEP lacks standing to challenge the trial court’s determination that the commission properly concluded that disclosure of the images would not pose a safety risk because the DPW did not appeal from that determination. I We first address the DEP’s claim that the commission improperly ‘‘reconfigured’’ Whitaker’s request when it ordered the DEP to provide Whitaker with copies of the photographic images licensed for use by the DEP, stripped of any associated metadata. The DEP contends that the commission’s order constituted an abuse of discretion because: (1) it is unclear whether Whitaker even wants the photographic images if they are stripped of any associated metadata; (2) the DEP has had no opportunity to determine whether it is feasible to strip the photographic images of the metadata; and (3) the DEP has had no opportunity to determine whether dis- closure of the photographic images stripped of the metadata would pose a significant safety risk. We agree with the DEP. We first address the DEP’s claim that the commission improperly ordered it to provide copies of the photo- graphic images stripped of the metadata to Whitaker when it was unclear whether he wanted or could use the records in that format. The following additional facts are relevant to our resolution of this claim. In his initial request to the DEP, Whitaker requested ‘‘[a]ll contracts with [the] DEP and Pictometry . . . for Pic- tometry services, data and software. All Pictometry imagery and any software required to view the Pictome- try images. Any DEP documents demonstrating compli- ance with [General Statutes § 1-211 (c)] . . . .’’ At the January 31, 2008 hearing before the commission, Whi- taker was asked whether he was requesting that the commission order the DEP to give him the metadata. He responded: ‘‘Yes, [the imagery is] useless without it. The imagery, not knowing where it is, is a jigsaw puzzle with no matching curves.’’ Whitaker also stated at a September 3, 2008 hearing before the commission, which was conducted after the commission had issued a proposed decision on the matter, that ‘‘I . . . don’t like having images [that] I can’t effectively use without licensing proprietary and expensive software from Pic- tometry.’’ He further stated that ‘‘[t]he metadata which has been found to be proprietary in this proposal for decision is the data which actually references where the camera was in relation to the [object] on the ground, which direction it was facing, which actually makes it possible to properly identify the image. . . . [W]ithout the metadata being included with the imagery, it’s actu- ally built into the imagery, it wouldn’t be possible to develop a different viewer to use these.’’ Later during the hearing, Whitaker stated that ‘‘if you give me 400,000 images with no ability to go anywhere, or find which image relates to which spot on the land, it’s useless.’’ General Statutes § 1-206 (b) (2) provides in relevant part: ‘‘In any appeal to the [commission] under subdivi- sion (1) of this subsection or subsection (c) of this section, the commission may confirm the action of the agency or order the agency to provide relief that the commission, in its discretion, believes appropriate to rectify the denial of any right conferred by the Freedom of Information Act. . . .’’ Accordingly, we review the commission’s ruling that the DEP must provide Whi- taker with copies of the photographic images stripped of the metadata for abuse of discretion.13 In support of its position that it was within its discre- tion to order the DEP to provide copies of the photo- graphic images stripped of any associated metadata, the commission relies on General Statutes § 1-211 (a),14 which provides in relevant part: ‘‘Any public agency which maintains public records in a computer storage system shall provide, to any person making a request pursuant to the Freedom of Information Act, a copy of any nonexempt data contained in such records, prop- erly identified, on paper, disk, tape or any other elec- tronic storage device or medium requested by the person, if the agency can reasonably make any such copy or have any such copy made. . . .’’ (Emphasis added.) The commission contends that this statute clearly authorizes it to deny a portion of a request for public records if some of the requested records are exempt. The commission also relies on this court’s decision in Hartford Courant Co. v. Freedom of Information Commission, 261 Conn. 86, 801 A.2d 759 (2002), for the proposition that it can order a public agency to separate exempt computerized data from nonexempt data and to produce only the nonexempt data. See id., 94–95 (when person submits request pursuant to § 1- 211 for nonexempt data contained in computerized record that contains both exempt and nonexempt data, ‘‘the disclosing agency must comply with such a request either by developing a program or contracting with an outside entity to develop a program’’ to separate exempt data from nonexempt data). We conclude that neither § 1-211 nor our decision in Hartford Courant Co. supports the commission’s position. Hartford Courant Co. is distinguishable from the present case because, in that case, the plaintiff had requested ‘‘an electronic copy of the public portion of all of the [department of public safety’s] criminal history records for all of the adults in those records.’’ (Empha- sis added.) Id., 89. Thus, the plaintiff’s request was clearly limited to nonexempt records. In contrast, in the present case, Whitaker requested ‘‘[a]ll Pictometry imagery and any software required to view the Pictome- try images.’’ During the course of the proceedings on Whitaker’s complaint, it became clear that Whitaker’s request for ‘‘Pictometry imagery’’ encompassed the metadata embedded in the computerized images. It also became clear that he believed that the images stripped of the associated metadata would be useless to him. Thus, unlike in Hartford Courant Co., the record in the present case supports the conclusion that Whitaker requested both exempt information and nonexempt information and that the requests were inextricably intertwined because the copies of the nonexempt images would be worthless to him without access to the exempt metadata. We agree with the proposition that, under some circumstances, the commission has the discretion to redact exempt information from other- wise public records requested pursuant to the act, and that it can order a party to produce computerized non- exempt records in a format other than the format in which they are maintained by the public agency. Under the facts of this case, however, we conclude that it was an abuse of discretion for the commission to require the DEP to provide copies of approximately 400,000 photographic images stripped of the associated meta- data to Whitaker in the absence of any evidence that he wants them or that he has any use for them in the format provided. The DEP also claims that the commission improperly ordered it to provide copies of the photographic images without providing an opportunity for the DEP to deter- mine whether it has the technical capability to strip the metadata from the computerized photographic images in its possession. The following additional facts are relevant to our resolution of this claim. At an August 27, 2008 hearing before the commission, one of the commissioners stated that ‘‘the testimony was that the [DEP] couldn’t strip out . . . all that data from the visual image and provide it to . . . Whitaker, only Pic- tometry could do that.’’ Counsel for Pictometry con- firmed that that was the case. When the commission inquired what it would cost to strip the metadata from the images, counsel for Pictometry responded that he did not know. A member of the commission then indi- cated that, if Pictometry were required to produce the images ‘‘all on one disk,’’ the cost ‘‘would be the cost of doing the disk.’’ The chairperson of the commission then asked Whitaker in what format the images could be produced. Whitaker responded that he believed that stripping the images of the metadata was inappropriate because it might require the DEP ‘‘to contract back with Pictometry for tens of thousands of dollars to strip out the metadata, and you’re going to have created such a high cost hurdle that none of these records are ever going to be disclosed.’’ The commission did not respond to this argument, however, and never made a finding as to whether or how the DEP could produce the copies. Thus, there is no evidence in the record that the DEP has the capability to provide copies of the photographic images stripped of the metadata. Indeed, the record supports the conclusion that only Pictometry would be able to do so. Accordingly, it may be impossible for the DEP to comply with the commission’s order.15 We conclude, therefore, that the commission abused its discretion by ordering the DEP to produce copies of the images stripped of the metadata without providing an opportunity for the parties to determine whether or how the DEP could comply with the order. Finally, we address the DEP’s claim that the commis- sion improperly ordered it to provide Whitaker with copies of the photographic images stripped of associ- ated metadata without providing an opportunity for the DEP and the DPW to determine whether doing so would pose a safety risk for purposes of § 1-210 (b) (19).16 That statute provides that, if the commissioner of public works, in consultation with the chief executive officer of a state agency, finds reasonable grounds to believe that disclosure of public records may result in a safety risk ‘‘of harm to any person, any government-owned or leased institution or facility or any fixture or appurte- nance and equipment attached to, or contained in, such institution or facility,’’ the act does not require disclo- sure of the records. General Statutes § 1-210 (b) (19); see footnote 3 of this opinion. As we previously have indicated in this opinion, Whitaker’s request encom- passed both the photographic images and the associ- ated metadata, and the DPW’s assessment of the safety risk was premised on the assumption that both the metadata and software were subject to disclosure. Accordingly, the DPW did not have an opportunity to consider whether the disclosure of the photographic images stripped of metadata would pose a safety risk. Under § 1-210 (b) (19), this safety determination is to be made by the DPW in consultation with the head of the relevant state agency, not by the commission. We conclude, therefore, that the commission abused its discretion by ordering the DEP to provide copies of the photographic images stripped of the associated meta- data to Whitaker without first providing the DEP and the DPW with an opportunity to determine whether their disclosure would pose a safety risk. Accordingly, we conclude that the matter must be remanded to the commission for further proceedings at which these issues may be addressed. II Because the issue will arise on remand if the commis- sion determines that Whitaker wants and is entitled to receive copies of the photographic images stripped of the metadata from the DEP, we next address the plain- tiffs’ claim that the commission improperly determined that federal copyright law is not a ‘‘federal law’’ for purposes of the federal law exemption set forth in § 1- 210 (a).17 We agree. Before addressing the merits of the plaintiffs’ claim that the commission improperly construed the federal law exemption set forth in § 1-210 (a), it is necessary for us to address an apparent inconsistency in the com- mission’s decision. Specifically, the commission stated in its decision that ‘‘the charge of $25 per image in addition to the [fee for the] two year licensing agreement would be an unreasonable charge and [the] DEP is not entitled to recoup those costs by charging the complainant for disclosure.’’ In addition, it found that ‘‘a public agency may not contract away its statu- tory obligations under the . . . [a]ct.’’ In support of this conclusion, the commission cited Lieberman v. State Board of Labor Relations, 216 Conn 253, 271, 579 A.2d 505 (1990), in which this court invalidated an agreement that was in conflict with certain provisions of the act. These statements would appear to suggest that the commission concluded that the licensing agreement was void to the extent that it authorized Pictometry to charge the DOIT or the DEP $25 for each copy of a photographic image provided to a member of the public pursuant to the act. Indeed, the commission argues on appeal that the provision of the licensing agreement requiring the DOIT or the DEP to pay Pic- tometry a copying fee of $25 per image is ‘‘in violation of the [act]’’ and is therefore ‘‘null and void.’’ Moreover, Pictometry’s appeal is premised on its belief that the commission’s decision ‘‘will serve to abrogate [its] rights under federal copyright law by preventing it from placing lawful restrictions on the copying and dissemi- nation of its copyrighted materials.’’ The trial court stated, however, that ‘‘Pictometry’s rights and remedies for injunctive relief and damages under 17 U.S.C. §§ 502 and 504, respectively, remain intact. So too, its contractual rights and remedies.’’18 The commission does not dispute this conclusion on appeal. Indeed, at oral argument before this court, the commission stated that Pictometry would have a private cause of action against the DOIT or the DEP for copy- right infringement if the DEP provided copies of the photographic images to Whitaker without paying the $25 per image fee pursuant to the licensing agreement.19 Thus, the commission appears to have concluded both that the act abrogates Pictometry’s rights under federal copyright law and the licensing agreement, and that Pictometry would be entitled to bring an action against the DOIT or the DEP to enforce those rights if the DEP provided copies of the photographic images to Whitaker and failed to pay Pictometry the $25 per image fee provided for in the licensing agreement.20 Because we are unable to reconcile these apparently conflicting rulings, we treat them for purposes of this opinion as alternate rulings. In other words, we assume that the commission intended to invalidate or to limit Pictometry’s rights under the licensing agreement and federal copyright law when it concluded that the DEP was required to provide copies of the photographic images to Whitaker, and that payment of the $25 per image copying fee to Whitaker in addition to the licens- ing fee would be ‘‘unreasonable.’’ We also assume, how- ever, that the commission further concluded that, even if the act does not abrogate Pictometry’s rights under federal copyright law, the act prohibits the DEP from passing on to Whitaker the $25 per image copying fee that it must pay to Pictometry. We begin our analysis of these issues with the stan- dard of review. ‘‘As we frequently have stated, [a]n agency’s factual and discretionary determinations are to be accorded considerable weight by the courts. . . . Cases that present pure questions of law, however, invoke a broader standard of review than is ordinarily involved in deciding whether, in light of the evidence, the agency has acted unreasonably, arbitrarily, illegally or in abuse of its discretion. . . . We have determined, therefore, that the traditional deference accorded to an agency’s interpretation of a statutory term is unwar- ranted when the construction of a statute . . . has not previously been subjected to judicial scrutiny [or to] . . . a governmental agency’s time-tested interpreta- tion . . . . Consequently, an agency’s interpretation of a statute is accorded deference when the agency’s inter- pretation has been formally articulated and applied for an extended period of time, and that interpretation is reasonable.’’ (Citations omitted; internal quotation marks omitted.) Longley v. State Employees Retirement Commission, 284 Conn. 149, 163–64, 931 A.2d 890 (2007). With respect to the issue before us in the present case, the commission previously concluded in an advisory opinion in another matter that copyrighted materials are exempt from the copying provisions of the act under the federal law exemption. Advisory Opinion, Freedom of Information Commission, No. 62 (1985) p. 2, available at http://www.state.ct.us/foi/Advisory_Opinions_& _Dec/AO_62.htm (last visited January 18, 2013) (materi- als ‘‘that are properly copyrighted under federal statute are generally exempt from the copying provisions of the [act]’’). Accordingly, because the commission’s posi- tion in the present case that the Copyright Act is not a ‘‘federal law’’ for purposes of the federal law exemp- tion has not previously been subjected to judicial scru- tiny and is not time-tested, but, indeed, is inconsistent with the position previously taken by the commission, our review is plenary.21 See Office of Consumer Council v. Dept. of Public Utility Control, 252 Conn. 115, 121, 742 A.2d 1257 (2000). ‘‘In making such determinations, we are guided by fundamental principles of statutory construction. See General Statutes § 1-2z;22 Testa v. Ger- essy, 286 Conn. 291, 308, 943 A.2d 1075 (2008) ([o]ur fundamental objective is to ascertain and give effect to the apparent intent of the legislature . . .).’’ (Internal quotation marks omitted.) In re Matthew F., 297 Conn. 673, 688, 4 A.3d 248 (2010). Section § 1-210 (a) provides in relevant part: ‘‘Except as otherwise provided by any federal law . . . all records maintained or kept on file by any public agency, whether or not such records are required by any law or by any rule or regulation, shall be public records and every person shall have the right to (1) inspect such records promptly during regular office or business hours, (2) copy such records in accordance with subsec- tion (g) of section 1-212, or (3) receive a copy of such records in accordance with section 1-212. . . .’’ None of the parties claim that the phrase ‘‘otherwise provided by any federal law’’ either plainly and unambiguously encompasses or excludes federal copyright law, and we conclude that it does not. ‘‘Accordingly, we may consider the statute’s legislative history, the circum- stances surrounding its enactment and the legislative policy that it was designed to implement in determining the meaning of that phrase.’’ State v. Jenkins, 288 Conn. 610, 621, 954 A.2d 806 (2008). This court repeatedly has held that ‘‘[t]he overarching legislative policy of the [act] is one that favors the open conduct of government and free public access to gov- ernment records. . . . The sponsors of the [act] under- stood the legislation to express the people’s sovereignty over the agencies which serve them . . . and this court consistently has interpreted that expression to require diligent protection of the public’s right of access to agency proceedings. Our construction of the [act] must be guided by the policy favoring disclosure and excep- tions to disclosure must be narrowly construed.’’ (Inter- nal quotation marks omitted.) Stamford v. Freedom of Information Commission, 241 Conn. 310, 314, 696 A.2d 321 (1997). ‘‘[T]he burden of proving the applicability of an exemption rests upon the agency claiming it.’’ (Internal quotation marks omitted.) Commissioner of Consumer Protection v. Freedom of Information Com- mission, 207 Conn. 698, 701, 542 A.2d 321 (1988). A With these general principles in mind, we first address the plaintiffs’ claim that the commission improperly determined that, because the Copyright Act is not a ‘‘federal law’’ for purposes of the federal law exemption, to the extent that the DEP’s obligations under the licensing agreement and federal copyright law conflict with its obligations under the act, its obligations under the act are controlling. This court previously has recognized that the federal law exemption embodies the legislature’s ‘‘willingness to defer to federal laws barring disclosure of otherwise disclosable information . . . .’’ Commissioner of Correction v. Freedom of Information Commission, 307 Conn. 53, 81, 52 A.3d 636 (2012). It is reasonable to conclude that this willingness stemmed from the legislature’s awareness of the consti- tutional principle that, when a federal law and a state law conflict and compliance with both laws is impossi- ble, the federal law will preempt the state law.23 Crosby v. National Foreign Trade Council, 530 U.S. 363, 372– 73, 120 S. Ct. 2288, 147 L. Ed. 2d 352 (2000) (‘‘[w]e will find preemption where it is impossible for a . . . party to comply with both state and federal law . . . and where under the circumstances of [a] particular case, [the challenged state law] stands as an obstacle to the accomplishment and execution of the full purposes and objectives of Congress’’ [citation omitted; internal quo- tation marks omitted]). In other words, it is reasonable to conclude that, when the legislature enacted the fed- eral law exemption, it intended, in the spirit of comity and deference to the supreme law of the land, to fore- stall any such preemption claims by providing in the first instance that the act does not apply to public records to the extent that any such application would conflict with federal law. In the present case, the commission concluded that the DEP could not ‘‘contract away its statutory obliga- tions under the [act]’’ by agreeing to give Pictometry the right to determine whether and under what condi- tions the copyrighted materials could be copied. Thus, the commission concluded that the provision of § 1-210 (a) conferring an unconditional right on ‘‘every person [to] . . . copy [public] records . . . or . . . [to] receive a copy of such records’’ conflicts with the provi- sions of 17 U.S.C. § 106 mandating that ‘‘the owner of copyright under this title has the exclusive rights . . . (1) to reproduce the copyrighted work in copies [and] . . . (3) to distribute copies . . . of the copyrighted work to the public by sale . . . or by rental, lease, or lending,’’ or to authorize these activities.24 As we have explained, however, the legislature intended that, to the extent that the application of the act conflicts with applicable federal law, the act does not apply. We con- clude, therefore, that, to the extent that the act and the Copyright Act impose conflicting legal obligations, the Copyright Act is a ‘‘federal law’’ for purposes of the federal law exemption. Accordingly, although the fed- eral law exemption does not entirely exempt copy- righted public records from the act, it exempts them from copying provisions of the act that are inconsistent with federal copyright law. In support of its conclusion to the contrary, the com- mission relies on this court’s decision in Lieberman v. State Board of Labor Relations, supra, 216 Conn 253.25 In Lieberman, this court considered the validity of an agreement between a public employee union and a town to destroy a union member’s employment record. This court observed that the retention of public records is subject to a comprehensive statutory scheme intended primarily to protect the rights of the public under the act. Id., 268. Under that scheme, ‘‘[o]nly certain indepen- dent library officials have been vested by the legislature with the authority to approve the destruction of public records.’’ Id., 271. Accordingly, this court concluded that ‘‘the destruction of a public employee’s discipline record is an illegal subject of collective bargaining’’; id., 261; and the agreement was, therefore, null and void. Id., 271. The commission contends that, because Pictometry’s photographic images are public records subject to the act, the principle that contracts that interfere with the public’s rights under the act are null and void is equally applicable to the provisions of the licensing agreement placing conditions on the DEP’s use of the images, and the provisions are therefore null and void. The short answer to this contention is that Lieberman does not control the present case because the public records at issue in that case did not come within the federal law exemption. As we have explained, the licensing agreement does not interfere with the public’s rights under the act because copyrighted records are exempt under the federal exemption from the copying provi- sions of the act that conflict with federal copyright law, which the licensing agreement embodies. The commission also relies on this court’s decision in Chief of Police v. Freedom of Information Commis- sion, 252 Conn. 377, 746 A.2d 1264 (2000), to support its position. In that case, the commission ordered the plaintiff to disclose certain records that were the sub- ject of discovery proceedings in a separate federal action, to which the plaintiff was also a party. Id., 383. The plaintiff contended on appeal that the records were exempt under the federal law exemption ‘‘because the Federal Rules of Civil Procedure already provide a legal process for [their] disclosure . . . .’’ (Internal quota- tion marks omitted.) Id., 399. This court rejected that claim. In doing so, this court stated that ‘‘linking a total federal exemption from the disclosure provisions of the act with a parallel reference to state statutes strongly suggests that the reference to ‘federal law’ was not intended to encompass federal litigation engendered issues of discovery. It suggests, instead, a reference to federal and state laws that, by their terms, provide for confidentiality of records or some other similar shield from public disclosure.’’ Id. The court then emphasized that ‘‘the only references in the entire legislative history of the act to the language in question are consistent with the suggestion that it was intended to refer to other federal and state laws that by their terms shield specific information from disclosure.26 There is nothing therein, therefore, that suggests that the legislature intended this very general language to encompass the kinds of individualized and possibly hypothetical deter- minations under federal discovery rules that the plain- tiff’s argument would suggest.’’ Id., 399–400. The commission contends that Chief of Police sup- ports the proposition that the federal law exemption applies only to federal statutes that, by their terms, bar the disclosure of certain public records, not to a federal statute, like the Copyright Act, that permits disclosure, but prohibits or places limits on the copying of public records subject to that law. We disagree. In Chief of Police, this court did not distinguish federal laws that exempt documents from the right to disclosure under the act from federal laws that exempt documents from the unconditional right to copy them. Rather, this court distinguished between federal laws that, by their terms, shield certain general types of documents from disclo- sure under freedom of information laws, such as laws barring the disclosure of i