Councilmember Chris Walsh said the ordinance would help reverse the attitude that underage drinking is a "rite of passage" in the community and not a health and crime issue.
The Supreme Court said a municipal court cannot place a defendant only on probation for an offense that has not been made punishable by a jail or prison sentence.
Mendoza-Cora now stands accused of six crimes: three charges of second-degree sexual abuse of a minor and three counts of third-degree sexual abuse of a minor.
The boy, who was five years old on the night of July 18, explained to jurors that a man took him across the river and sexually abused him before leaving him by himself near Wyoming Boulevard.