City Hall officials will investigate whether former Police Commissioner Bill Bratton and other ex-top cops should have placards that allow them to park illegally.

“We’re looking at the issue,” Mayor Bloomberg’s spokesman, Stu Loeser, said yesterday after The Post reported that Bratton was using an NYPD placard. Rules governing parking placards state that the user has to be on “official” NYPD business.

But the Police Department has long offered the perk to its former leaders, spokesman Paul Browne said yesterday.