The Florida Supreme Court will decide whether cities that used red light cameras to collect fines did so illegally before the Legislature approved the devices in 2010.
Justices heard arguments Thursday in a case that involves red light cameras in Aventura and Orlando.
Lawyers for drivers argued that state law requires uniform traffic law enforcement and that the cities didn't have the right to set up their own fine system outside of the law.
Lawyers for the cities argued that they did have the right to set up a parallel enforcement system.
Justice Charles Canady said state law seemed to clearly spell out that municipalities couldn't institute their own traffic fine system.
Justice Barbara Pariente indicated her concern was whether municipal fines exceed fines allowed under state law.