An overview of the exhibitors and customers at the cannabis expo and job fair at the Holiday Inn Capitol Hill in Washington on Feb. 28. (Linda Davidson/The Washington Post)

A D.C. Council committee on Wednesday unanimously advanced legislation to ban employers in the nation’s capital from testing prospective employees for marijuana until after a job offer is made.

But the law won’t free employees to light up without consequences. Employers will retain the right to screen for drugs after making a job offer — and to enforce their own drug policies with employees. The law’s primary function, supporters said, is to give prospective workers the time to prepare for a job in a workplace that prohibits marijuana use.

“It’s time for employers and employees to get used to the idea of marijuana being legal,” said Vincent B. Orange (D-At Large), referring to a voter-approved ballot measure that took effect last Thursday. The measure legalized the possession, smoking and cultivation of the drug, albeit with heavy restrictions on public use.

The bill, which Orange sponsored, amounts to a first in what could perhaps be dozens of legal changes council members say they expect to undertake in coming months as they grapple with balancing marijuana’s new status as a legal intoxicant in the District against decades of laws aimed at preventing the use of the drug and punishing those found with it. Most council members have indicated that they will approve it.

Late last year, foreseeing the hiring process as the first pitfall, Orange persuaded council colleagues to approve a temporary block on such screenings, but that measure will expire soon. He said a permanent measure was needed quickly to draw employers’ attention to the matter.

Nothing in Orange’s bill upends the prohibition on federal workers using marijuana. Government contractors who must certify a drug-free workforce and those who hire for sensitive security positions could continue to test for marijuana before extending a job offer.

Employers also could still set their own terms for employment and require random or periodic drug testing of employees.

The D.C. Chamber of Commerce said last week that it would not oppose the legislation as long as employers could continue to require drug testing after making a conditional offer of employment.

According to marijuana advocates, five states — Arizona, Connecticut, Delaware, Maine and Rhode Island — have similar protections but only for those using medical marijuana.

Council member Elissa Silverman (I-At Large), who voted for the bill, said she thinks it strikes the right balance.

“Recreational use should not be a barrier to employment,” she said.

The bill would require Mayor Muriel E. Bowser’s administration to “establish a public information campaign aimed at educating the public on the impact of marijuana use and abuse.”

Under the law, Bowser (D) would also have to report to the council on a promise she made last week: to begin to address marijuana legalization in public classrooms. Within six months of passage, the legislation would require an analysis of the “type, frequency, provider, and school grade level of health education programs in public schools related to substance abuse, including programs designed to address alcohol, tobacco, and marijuana use.”

Orange, however, said the prime goal is to begin to address potential discrimination in the hiring process.

“It is imperative that people who choose to use marijuana are not stigmatized when looking for employment,” his committee report on the bill concluded. D.C. law, it said, needs to “ensure that District residents are able to act within the bounds of the law and not be discriminated against.”

Orange said he looked forward to full regulation and taxation of the drug in the District. Until then, he said, laws like those limiting marijuana testing for job applicants would help the city find its way forward.

“We’re in the preliminary stages,” Orange said. “We are going to learn a lot as we go along.”