Miami-Dade Circuit Court Judge Jerald Bagley ruled that Aventura use of red-light cameras is in violation of state law. An article in the Miami Herald states:
The ruling came in a lawsuit filed by a motorist who argued that only the state Legislature can pass laws regarding traffic violations. Cities have gotten around the lack of authorization by citing red light runners with a code violation, rather than a traffic ticket.
I personally experienced being cited for such a "code violation" after a short visit to Naples. The SunSentinel stated:
Invoking opinions issued by the state attorney general in 1997 and 2005, Miami-Dade Circuit Judge Jerald Bagley said traffic laws are the purview of the state and that police officers should witness — and then issue tickets to — red-light runners.
Attorney General Opinion AGO 97-06, released on January 24, 1997 and titled "Traffic citations, use of unmanned cameras" can be found HERE. Attorney General Opinion AGO 05-41, released on July 12, 2005 and titled "Traffic, use of unmanned cameras" can be found HERE.