After Massachusetts's vote to decriminalize possession of small amounts of marijuana, top law enforcement officials are scrambling to figure out what they need to do to put the law into effect - despite their efforts to defeat it at the polls.

Attorney General Martha Coakley, who joined all 11 of the state's district attorneys in opposing the ballot question, said Wednesday that she was working to determine exactly what it will require the legal system to do.

"Question 2's passage not only authorizes the decriminalization of small amounts of marijuana, but also establishes a parallel civil regulatory structure that does not currently exist," Coakley said in a written statement. "At this time, we are reviewing all of the implications of the new law and whether further clarification or guidance is needed."

Massachusetts becomes the 12th state in the country to decriminalize possession of small amounts of marijuana. The measure passed Tuesday with 65 percent of voters supporting it and 35 percent opposed.

Under the state's constitution, a ballot question approved by voters becomes law 30 days after an election.

The courts have defined the end of an election as the date on which the Governor's Council certifies voting results. That typically happens during the last week of November or the first week of December.

Until the new law takes effect, marijuana possession will be considered a crime, Coakley said.

Possession of small amounts of marijuana in the state is now punishable by up to six months in jail and a $500 fine.

Once the new law takes effect, anyone caught with an ounce or less of marijuana will face a civil offense punishable by a $100 fine. They will also have to forfeit the marijuana. Anyone under 18 will also have to give up the drug, but they will face a stiffer $1,000 fine unless they complete a drug awareness program.

Hampden (Mass.) District Attorney William Bennett said Wednesday that he'll drop all pending charges of possessing an ounce or less of marijuana and won't prosecute new ones in order to focus instead on drug dealers.

"I'm going to act as if the law were in effect now," he told The Republican of Springfield, Mass. He said he doesn't know how many charges would be dismissed, but it's not a significant number.

Thomas Kiley, a lawyer representing the Committee for Sensible Marijuana Policy, which pushed the ballot question, said the two months will give the state time to make the adjustments needed to conform to the new law, including the creation of new drug-awareness programs by the Department of Youth Services.

Supporters of the ballot question said the new law will spare thousands of people from having a criminal record, which can make it harder to get a job, obtain a student loan or gain access to public housing. Supporters also said taxpayers would save $30 million in costs associated with marijuana arrests.

Opponents, led by the district attorneys, had warned the measure could lead to more drug abuse among young people.