Chicago recently joined the ranks of cities attempting to restrict photography of its trains. Union Pacific Railroad recently banned photography of its trains from Metra station platforms, citing security concerns since “recent incidents around the world.”

In 2004, the MTA attempted a similar restriction, banning photographs on subway trains. As in New York, though, complaints from Chicago residents have already urged a “clarification” from Metra. Whereas photos at any platform were initially banned, Union Pacific instead said photographs were allowed, but “suspicious activity would also allow any employee to question the photographer.”

It remains to be seen if, as in New York, this loosely defined ban will continue to spell confusion and frustration for the city’s photographers.