The American Civil Liberties Union of New Jersey has filed an open records request to learn more about NJ Transit's policies regarding its audio and video surveillance of its light rail trains.

NJ Transit has acknowledged that it monitors and records the conversations of light-rail passengers but pointed to instances of terrorism around the world, including last month's deadly attack on a Brussels airport and metro station, as the reason behind the surveillance, which the agency says it is within its rights to do.

The agency said in a statement that the New Jersey Transit Police Department "is responsible for managing access to the recordings for limited investigative purposes" but would not provide specifics as to whether the audio and video footage are recorded continuously, who has access to the footage, how the recordings are stored, and how long they are maintained. The ACLU requested this information in its OPRA request along with samples of audio recorded on the Riveline, Hudson-Bergen and Newark lines.

“This kind of surveillance is chilling on so many levels – it’s chilling to know that NJ Transit is listening to us without sharing any details, and it chills free speech to know these microphones are always on,” said ACLU-NJ Deputy Legal Director Jeanne LoCicero. “This kind of intimate surveillance changes the character of our public spaces, and it creates a kind of society that doesn’t reflect who we are as Americans."

Signs are posted in stations warning of the surveillance which offers no other explanation of their intended use.

NJ Transit said it had no comment on the ACLU's request.