(Dayna Smith for The Washington Post)

Rep. Trey Gowdy (R-S.C.), the new head of the House Oversight and Government Reform subcommittee with jurisdiction over District affairs,came to the Henry J. Daly Building last Monday to sit in on a daily crime briefing, followed by a sit-down with Lanier.

Lanier first met Gowdy some weeks ago, when he visited the John A. Wilson Building to meet with Mayor Vincent C. Gray (D). “He asked if he could come over sometime,” she said.

Gowdy is a former federal prosecutor and elected state’s attorney from Spartanburg. In a January interview with The Washington Post, Gowdy expressed curiosity about the District’s novel criminal justice system, given his background.

“He’s trying to get into the things he’s familiar with,” Lanier said Friday. “It’s so complicated for someone who’s not from D.C.” — a reference to the District’s un­or­tho­dox law enforcement arrangement.

Not only are federal crimes prosecuted by the U.S. Department of Justice, but most local misdemeanors and all local felonies are prosecuted by the feds, too — in D.C. Superior Court, which is chartered and funded by Congress. But local crimes are mainly investigated by the Metropolitan Police Department, which reports to the mayor. Adding to the complexity: The MPD shares policing duties with an alphabet soup of law enforcement agencies in the District, including the U.S. Capitol Police, the Park Police, the Secret Service Uniformed Division and dozens of other agencies.

“I think he came away with a better understanding of the complexity of how things work,” Lanier said. “It’s more complicated here.”

Law and order in the District has long been a matter of keen congressional interest. Perhaps the uneasiest period in District-congressional relations since the advent of home rule came in the early 1990s, when a crack epidemic decimated city neighborhoods — and Tom Barnes, a 25-year-old aide to Sen. Richard C. Shelby (then-D-Ala.), was randomly shot to death. Barnes’s 1992 murder prompted calls from the Hill to impose the death penalty for the first time under home rule.

Gowdy’s spokesman, Robert Hughes, said in an e-mail that his boss “greatly enjoyed” the visit to MPD headquarters and was “thoroughly impressed by the professionalism and initiative demonstrated by Chief Lanier and her Department.” The briefing, he relayed, was “well-organized” and “productive.”

“He was a fan of Chief Lanier before the meeting — and walked away with an even greater respect and appreciation for her outstanding service,” Hughes said.