A federal judge says the Environmental Protection Agency’s use of personal email accounts may have been aimed at skirting public disclosure requirements.

U.S. District Judge Royce Lamberth ruled Wednesday that a conservative public interest law firm, the Landmark Legal Foundation, can question and obtain records from EPA officials as part of the firm’s lawsuit against the federal agency, citing the Freedom of Information Act.

The judge granted Landmark the right to seek the information to determine whether top EPA officials used personal email accounts to conduct official business — and whether the agency initially excluded those accounts from Landmark’s Freedom of Information request.

“The possibility that unsearched personal email accounts may have been used for official business raises the possibility that leaders in the EPA may have purposefully attempted to skirt disclosure under the FOIA,” wrote Lamberth.

He said the possibility that the agency purposefully excluded the top leaders of the EPA from the FOIA search, at least initially, “suggests an unreasonable and bad faith reading of Landmark’s FOIA request and subsequent agreement to narrow its scope.”

In the lawsuit last year, the foundation asked for any records that indicated the EPA was delaying the announcement of new environmental regulations until after last year’s presidential election.

In June, it was revealed that some top Obama administration officials were using secret government accounts to conduct official business. Sen. John McCain of Arizona, the senior Republican on the Senate’s Permanent Subcommittee on Investigations, has said the practice undermines congressional oversight and complicates access to records under FOIA.

Late last year, some EPA critics accused former Administrator Lisa Jackson of using an email account under the name “Richard Windsor” to sidestep disclosure rules. The EPA said emails Jackson sent using her Windsor alias were turned over under open records requests. That email account is an EPA.gov email address, not a personal one.

The EPA did not immediately respond to requests for comment Thursday.