GRAND RAPIDS, MI -- A Kent County judge today ruled that a voter-approved amendment to decriminalize marijuana is valid.

At the same time, Judge Paul Sullivan dismissed Kent County Prosecutor William Forsyth's effort to nullify the charter amendment.

Sullivan on Monday, May 6, ruled that possession of small amounts of marijuana in Grand Rapids can be handled as a civil infraction as voters earlier decided.

Forsyth had argued that the amendment conflicts with Michigan laws that classify marijuana possession as a misdemeanor. He also said it would interfere with his responsibilities as county prosecutor.

Even before Sullivan's ruling today, Grand Rapids Police began following the charter amendment on May 1 and started writing civil infractions.

In his ruling, Sullivan wrote: "The voters of Grand Rapids had the power to amend the city charter and plaintiff has failed to show that any section of the charter amendment necessarily conflicts with state law."

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He went on to write: "It is still a crime for one to possess, control, use or give away marijuana in Grand Rapids. The charter amendment merely creates a civil infraction in the city and directs the city's police resources away from some of these laws."

Sullivan noted that other law enforcement agencies may still have "jurisdiction" in Grand Rapids and are "free to investigate and prosecute any marijuana-related offenses occurring in Grand Rapids.

"Those who violate state and/or federal laws relating to marijuana still risk the possibility of criminal prosecution for violation of the laws, even within the confines of the city of Grand Rapids."

E-mail John Tunison: jtunison@mlive.com and follow him on Twitter at twitter.com/johntunison