D.C. Police Chief Cathy L. Lanier announced Thursday that she has ended citywide vice units and has shifted the department’s approach and targets of drug investigations.

At a public forum Thursday night and in e-mails, Lanier said that D.C. Police will focus on drugs that pose a major public safety threat and on figuring out how those drugs are distributed.

“Our main goal is the supply. We don’t want to focus police efforts on just people who are addicted. We want to be focusing on the people who are bringing the stuff in,” Lanier told about three dozen residents at a community forum on Minnesota Avenue NE.

The shifts in strategy are expected to eliminate many of the plain-clothes operations that police have used for decades to target open-air drug markets that were magnets for drive-by shootings and other violence. Lanier said that drug markets have changed since the early 2000s, when police tracked 210 active markets. Today, few drug markets operate in the open.

PCP, club drugs such as MDMA, also known as ecstasy, and other synthetic drugs are the main threats to public safety, Lanier said. She added that those drugs require a new approach.

“That’s not to say there’s not drugs being sold on the street, because there are, but the drug dealers are much more sophisticated than they used to be and it’s not going to [be] the same tactics from us,” Lanier said.

With the shift, Lanier said high-level and more sophisticated drug operations will be investigated by detectives from the Narcotics and Special Investigations Division. Police will continue to do undercover operations, she said. But as much as possible, Lanier wants police to be identifiable and clearly marked when making arrests, not being used as plain-clothes jump-out squads.

“Our criminal environment is changing rapidly. We have to keep up,” Lanier said in an interview. “This is a biggie for us.”

Ward 5 D.C. Council member Kenyan McDuffie, who chairs the council’s judiciary committee, said Lanier’s new initiative could help alleviate reported tensions that arise when officers don’t identify themselves to residents.

“It will help to the extent that the residents can identify the officers they encounter in the community,” McDuffie said. “I think anything that the chief puts in place to try and build relationships between the community and police is something we should be welcoming.”

Sheila Carson Carr, an Advisory Neighborhood Commission representative in Ward 7, said she wants a more proactive police approach in her neighborhood. And if more uniformed officers on the street will cut down on crime, she’ll get behind it.

“I don’t have any problem with it if it works,” said Carson Carr. “It sounds feasible, but we’re going to be watching.”