Ordinances passed by Nashville and Memphis this year that gave police discretion to hand out lighter civil citations for possession of small amounts of marijuana violate state statute and therefore can't stand, according to Tennessee Attorney General Slatery.

Slatery issued the opinion Wednesday, arguing that municipalities are preempted by state law on the matter and thus the ordinances are not enforceable.

Mayor Megan Barry in September signed into law an ordinance passed by the Metro Council to give Nashville police the option of reducing the penalty for people who are found in knowing possession of a half-ounce of marijuana or less to a $50 fine or 10 hours of community service.

The city of Memphis later passed a similar ordinance.

Under Tennessee law, violators of possession of small amounts of marijuana face a Class A misdemeanor charge that is punishable by up to one year in jail and a $2,500 fine.

Supporters of Nashville’s marijuana legislation have argued the local ordinance works within the confines of state law, likening the measure to Metro’s laws for litter and seat belts, both of which have penalties that are not as severe as those outlined in state law.

But Slatery argues that the ordinance is preempted by state law, citing the Tennessee Drug Control Act of 1989, which makes “simple possession or casual exchange” of a controlled substance unlawful. He also cites the state statutes concerning both possession and distribution of small amounts of marijuana, which outlines they are Class A misdemeanors.

"A municipal ordinance that attempts to regulate a field that is regulated by state statute cannot stand if it is contradictory to state law," Slatery says in the opinion.

State Sen. Brian Kelsey, R-Germantown, and Rep. Ron Lollar, R-Bartlett, requested the opinion.