A majority of D.C. Council members on Wednesday signed on to a bill to decriminalize possession of up to an ounce of marijuana, giving the proposal considerable momentum as the body prepares to consider the matter this fall.

Council members Tommy Wells (D-Ward 6) and Marion Barry (D-Ward 8) drafted the bill, which would make possession of the drug subject to a $100 civil fine.

Six other council members signed on as co-sponsors — Democrats Anita Bonds (At large), Jim Graham (Ward 1), Jack Evans (Ward 2), Kenyan McDuffie (Ward 5), Mary M. Cheh (Ward 3) as well as Independent David Grosso (at large).

“Lets get this done and stop arresting, mostly black men, for small amounts of marijuana,” Barry said.

Wells, the chairman of the Public Safety and Judiciary Committee, said the strong support leaves him optimistic the proposal can be put up for a formal vote before Christmas.

But in a statement, Police Chief Cathy Lanier urged a “robust discussion,” calling it a “significant issue.” Lanier said she has concerns about the risks marijuana poses for children, as well as potential conflict with federal law.

“It is important for the community to recognize that some of the information being used as an argument for decriminalization is flawed,” said Lanier, referring to a report by the American Civil Liberties Union released last month that showed the District outranked the 50 states in per-capita marijuana arrests.

The study also found that African Americans in the District were eight times more likely than whites to be arrested for marijuana possession.

Council member Yvette Alexander (D-Ward 7) also said she will not be supporting the proposal She questioned Barry and Wells’s argument that decriminalization will help more District residents land jobs.

“When you apply for a job, and there is a drug test, and you come up positive, you still can’t get the job,” Alexander said. “So why would we make it one step closer for people to smoke marijuana?”

At a news conference earlier Wednesday, Wells said his legislation is designed to lessen the impact that the nation’s drug laws have on young adults who become ensnared in the criminal justice system.

“We are going to really acknowledge that the war on drugs, in particular marijuana, have worked to criminalize many of your youth and disadvantaged them from being able to get jobs,” Wells said. “Once you have a marijuana charge on your record, you can not participate in, certainly the construction boom that is happening all over the city, and it works to stigmatize people … and it disadvantages them from jobs.”

Under current law, possession of up to an ounce of marijuana in the District is a misdemeanor punishable by up to a $1,000 fine and six months in jail.

Wells’s bill would make possession of up to an ounce similar to a speeding ticket that does not result in a criminal record. Minors would have to attend a drug awareness class, and their parents would be notified.

Grosso plans to go a step further by introducing a bill this fall to legalize, tax and regulate marijuana in the District.

Mayor Vincent C. Gray (D) and Council Chairman Phil Mendelson (D) are skeptical of efforts to decriminalize or legalize marijuana, fearing it could result in backlash from Congress.

But the ACLU and several marijuana advocacy groups joined Wells Wednesday to press for decriminalization.

“This bill is about human beings; it’s about people, communities, and families whose lives have been destabilized and individual lives derailed,” said Seema Sadanandan, of the ACLU.

This article has been updated.