(Reuters) - Marijuana advocates' hopes that the U.S. capital would easily follow in the footsteps of Denver or Seattle in clearing the way for lawful pot use are set to go up in smoke this week.

Voters in the District of Columbia last year passed a measure clearing the way for pot possession, but members of Congress have used their power over the city to prevent local officials from coming up with any plan to let the drug be sold legally for recreational purposes.

With the congressional review period for the new measure set to expire on Wednesday, District of Columbia pot users will be left in a murkier position than those in Colorado and Washington state, which fully legalized marijuana last year.

"What you're going to have on Feb. 26 is an anomaly. You can possess a small amount ... but you can only get it, I guess, illegally," said Eleanor Holmes Norton, Washington's non-voting representative in Congress. "It's going to be an incomplete reform."

The uncertainty stems from Initiative 71, a referendum approved by 65 percent of District voters in November. A key argument by supporters was that marijuana laws unfairly victimized black people in Washington, who represent about half the city's population.

Initiative 71 allows possession of up to two ounces (56 grams) of marijuana and six pot plants, three of them mature. It allows the gift of up to one ounce (26 grams) of pot, but has no provision for sales.

District finance officials have estimated the local market, including medical marijuana, could be worth $130 million a year.


Initiative 71 ran into opposition in Congress, which has oversight over the heavily Democratic District of Columbia. Republicans inserted a provision in a spending bill in December that barred the District from using any funds to legalize pot.

Democratic Mayor Muriel Bowser has contended that the District of Columbia can move forward with legalization because voters enacted the measure before Congress stepped in.

But Representative Jason Chaffetz, the chairman of the House of Representatives Oversight and Government Reform Committee, has vowed to block legalization, citing the December spending bill.

"I respect the people who live here and most everything passes through without a problem. But the idea that this is going to be a haven for pot smoking, I can't support that," Chaffetz, a Utah Republican, told CNN this month.

When District of Columbia Council committees debated a bill to regulate marijuana like alcohol, lawmakers downgraded the Feb. 9 hearing to an informal "roundtable discussion" to avoid raising objections from Congress.

Chaffetz responded last week by sending a letter to the council asking for an explanation of the hearing and documentation, including details on the salaries of any city employees who took part.

Asked what Bowser, the mayor, will do when Initiative 71 takes effect on Thursday, a spokeswoman said, "Right now, it's on a to-be-determined basis."


A spokesman for District Attorney General Karl Racine declined to give details about what advice he had offered officials about the new pot law.

But Racine, police and other officials "are very much committed to ensuring the transition to the regime enacted by Initiative 71 takes place in an orderly manner," he said in an email.

Dr. Malik Burnett, policy manager with the pro-legalization Drug Policy Alliance, said he expected District of Columbia officials would figure out how to regulate sales and taxes despite congressional opposition.

"This process will be worked out over the next couple of weeks or months. I'm pretty optimistic," he said.

Burnett said it was unlikely that users of medical marijuana from outside the District of Columbia could get pot in Washington since the city lacked reciprocity accords for medical marijuana use.

Despite marijuana's uncertain status, District of Columbia entrepreneurs are gearing up for legalization.

A convention in Washington the coming weekend sponsored by ComfyTree, a Michigan cannabis consultancy, has drawn at least 600 registered visitors and 40 exhibitors, said Tiffany Bowden, the company's co-founder.

"Definitely, the District of Columbia is the next frontier for legalization," she said.

The District of Columbia now has one of the lightest U.S. penalties for pot possession. Marijuana possession remains illegal under federal law, but the Obama administration's Justice

Department has generally taken a hands-off approach in states where its sale is properly regulated.

(Reporting by Ian Simpson; Editing by Scott Malone and Mohammad Zargham)