Members of San Francisco’s Board of Supervisors may have found a loophole in transparency laws that would hide certain messages from the public. Colleagues in City Hall encouraged board members to use ephemeral messaging app Telegram to keep their communications private, according to news website The Information. The Information reported observing several supervisors and their aides appearing as ‘active’ on the app throughout the day, sometimes using the app hourly. Reports indicate officials are using the app on their private phones, which could make an audit more difficult.

There’s no legal precedent for this, said Aaron Mackey, a Frank Stanton legal fellow at the Electronic Frontier Foundation, but it’s potentially illegal and definitely against the spirit of the public records laws that apply to San Francisco public officials.

“There are three laws that are applicable here,” Mackey said. “The biggest one is the California Public Records Act (CPRA). The second is the San Francisco Sunshine Ordinance. And the third is records retention schedules that are created by the state and by local municipalities regarding the retention and destruction of records.”

According to an official summary of the California Public Records Act, the primary purpose of the law, backed by court rulings, is to give the public an opportunity to monitor how their government is functioning. There are records that are exempt from CPRA requests, usually for issues of privacy and security, but the general theme of the law is that if the public requests a record, the government entity is required to deliver it. Because messaging apps like Telegram do not leave a record behind to be delivered to the public, however, a gray area emerges.

“If anyone is writing things about the government’s business, then it falls within the Public Records Act,” Mackey said. “And it also falls within the Sunshine Ordinance because that adopts for its definition what it calls ‘public information.’ … But if you look at the records retention requirements and how the attorney general has interpreted those, you’re supposed to keep documents that are either required to be kept by law or that chronicle the actions of public officials. The principle is that you want to keep those records not just for transparency, but for history and for the institution’s own future knowledge.”

In 2012, New York Gov. Andrew Cuomo grabbed headlines by refusing to use email, requiring anyone contacting him to use BlackBerry’s PIN-to-PIN function, which establishes a direct connection between phones and, just as with ephemeral messaging apps, does not leave a record that the public can later request. Whether the governor was being prudent, making a point about privacy or the rights of the government, or hiding something he didn’t want the public to know about was never proven.

In the case of the San Francisco Board of Supervisors, the public is unlikely to give officials the benefit of the doubt. Mackey wouldn’t comment on whether the board was doing anything unsavory, but that they were acting outside the best interests of both the public and government itself.

“The bottom line is that it definitely appears as if they are using technology in a way that thwarts transparency,” he said. “I think that if they’re conducting public business, they should be maintaining records of that and they should not be communicating in a way that frustrates access to public deliberations.”

Telegram’s use has been featured in the media recently for both the ephemeral nature of its messages but also its encryption features, a technology popularized by the ongoing San Bernardino shooter case, in which Apple refuses to assist the FBI by creating a tool that would crack iPhone encryption.

Telegram reported 100 million monthly active users last month, with 15 billion messages delivered daily. Terrorist group ISIS reportedly used the technology to spread propaganda and recruit fighters. Last year, Telegram reported blocking 78 ISIS-related channels across 12 languages, alongside a reporting feature to discourage such use of the app.

Representatives from the San Francisco Board of Supervisors were contacted for comment on this story, but did not respond by the deadline.