DENVER - Anthony Orozco, 19, a community college student and soccer player in southeastern Colorado, is facing criminal charges for something that will soon be legal across this state: the possession of a few nuggets of marijuana and a pipe he used to smoke it.
Mr. Orozco said that one day in September he and a few friends were driving in Lamar, on the plains near the Kansas border, when they were pulled over. After the police officer found marijuana in the car, Mr. Orozco was issued a summons for possession and drug paraphernalia - petty offenses that each carry a $100 fine - and given a court date.
"We get treated like criminals," Mr. Orozco said.
But is he one? In the uncertain weeks after Colorado's vote to legalize small amounts of marijuana for recreational use, the answer in hundreds of minor drug cases depends less on the law than on location.
Hundreds of misdemeanor marijuana cases are already being dropped here and in Washington State, which approved a similar measure. Police departments have stopped charging adults 21 years and older for small-scale possession that will be legally sanctioned once the laws take effect in the coming weeks.
But prosecutors in more conservative precincts in Colorado have vowed to press ahead with existing marijuana cases and are still citing people for possession. At the same time, several towns from the Denver suburbs to the Western mountains are voting to block new, state-licensed retail marijuana shops from opening in their communities.
"This thing is evolving so quickly that I don't know what's going to happen next," said Daniel J. Oates, the police chief in Aurora, just east of Denver.
Regulators in Washington State are also scratching their heads. And they are looking for guidance on how to set up a system of licenses for production, manufacturing, distribution and sales - all by a deadline of Dec. 1, 2013. They say that Colorado, for better or worse, is ahead of most states in regulating marijuana, first for medical use and now recreationally.
"Colorado has a more regulated market, so they will be a good guide," said Brian E. Smith, a spokesman for the Washington State Liquor Control Board. But no place or system, Mr. Smith conceded, can do more than suggest what might work. "There's no real precedent for us to follow," he said.
Washington's law, called I-502, takes effect on Dec. 6, which also leaves a year of limbo during which the state licensing system will not yet exist, but legalized possession will. And there are thorny mechanical questions that must be resolved during that time, like how to balance the state's mandate of "adequate access" to licensed marijuana with its prohibitions on cannabis businesses within 1,000 feet of a school, park, playground or child care center.
"Nowhere will it be more difficult to site a licensed cannabis business than in urban areas, particularly in the Seattle metropolitan area," said Ben Livingston, a spokesman for the Center for Legal Cannabis, a recently formed research group.
On Nov. 21, Chief Oates in Aurora sent his officers an e-mail announcing that the city attorney would no longer be prosecuting small marijuana violations for anyone 21 years or older, and that the police would stop charging people for those crimes "effective immediately."
Chief Oates said that the police would enforce city codes regulating medical marijuana growers, and that they would still pursue drug traffickers and dealers.
In northern Colorado's Weld County, the district attorney, Ken Buck, represents a stricter view. After the vote, he said his office would continue pursuing marijuana possession cases, mostly as a way to press users into getting treatment. Right now, 119 people face charges of possessing two ounces or less of marijuana, though many are facing other charges.
"Our office has an obligation to prosecute offenses that were crimes at the time they occurred," Mr. Buck said in a statement.
The response has been complicated even in places like rural Mesa County, where voters rejected the marijuana initiative. The police in Grand Junction, the county's largest city, are no longer citing adults for possession of small amounts. The county's district attorney, Pete Hautzinger, supported that decision, but also decided not to dismiss all of the pending possession cases.
"I do not think I'm wasting my time continuing to enforce the law until it changes," he said.
Although 55 percent of Colorado voters supported the measure, bringing recreational marijuana into the folds of government and the legal system was never going to be simple. And the contradictory reactions across the state lay bare a deep ambivalence among local officials about the state's big green experiment.
"It's a cultural barrier" with district attorneys, said Sean McAllister, a Denver lawyer who represents marijuana defendants and is a local spokesman for the National Organization for the Reform of Marijuana Laws.
"They spent so much of their lives prosecuting people that they still don't really accept that this is legal," he said.
As the first states to treat small amounts of marijuana like alcohol, Colorado and Washington are poised to become national test cases for drug legalization. As advocates and state officials plan for a new frontier of legalized sales, they are also anxiously awaiting direction from the federal government, which still plans to treat the sale and cultivation of marijuana as federal crimes.
Advocates for legalized marijuana are hoping the Justice Department yields. Despite some high-profile arrests of medical marijuana patients and sellers, the federal government has mostly allowed medical marijuana businesses to operate in Colorado, Washington and 16 other states.
While drug agents will probably not beat down doors to seize a small bag of the drug, they are likely to balk at allowing the state-regulated recreational marijuana shops allowed under the new laws, said Kevin A. Sabet, a former drug policy adviser in the Obama administration.
Several cities in Colorado are not waiting for federal authorities to act. Even before Election Day, some local governments approved moratoriums on any new marijuana shops, even though it will be about a year before any can open. Last week, the western city of Montrose took up a six-month ban, and is likely to pass it next week.
"We don't want to be put in a position where we license somebody and then have a big federal issue," said Bob Nicholson, a City Council member. "Our community voted against this amendment. We're looking at what the community voted for versus what the state voted for. There's an awful lot of questions."