A security guard opens the door for customers at Tropicalia, at the corner of 14th and U streets NW. (Sarah L. Voisin/The Washington Post)

Applications to become the District’s first nightlife director came in from across the country and around the world, but Mayor Muriel E. Bowser selected a lead investigator from her own liquor board to take on the city’s “after-hours economy” — noise, crime, rats and all.

Shawn Townsend, who ran a team of six investigators at the Alcoholic Beverage Regulation Administration, will take over the city’s inaugural Office of Nightlife and Culture next month.

Bowser (D) introduced him Wednesday during the launch of the Dupont Circle Business Improvement District.

“Across the city, we need somebody focused on our nighttime economy because it is a big contributor to everything we’re able to do in the government,” she said.

Townsend’s job at the helm of the new office will be “to promote our nighttime economy, to help deal with any conflicts that arise in a nightlife economy and to make sure we’re looking at all the different ways that we can think differently about attracting people and visitors to support what happens to D.C. after dark,” Bowser said.

The mayor’s office declined to make Townsend available for comment Wednesday.

In his role as an investigator for the ABRA, Townsend led routine inspections of bars, restaurants and stores to ensure that they were compliant with city liquor laws. He helped prevent the sale of alcohol to minors and investigate accusations of misconduct.

This familiarity with “nightlife establishments” was among the qualities Bowser extolled about Townsend on Wednesday.

He has worked for the ABRA since 2014. Before that, he held positions with the D.C. Office of Police Complaints and D.C. Public Schools. Townsend helped launch a bar of his own in Charleston, S.C., before moving to the District.

His new role will be wide-ranging, keyed on responding to the needs of businesses open between 5 p.m. and 2 a.m. — including bars, restaurants, theaters, clubs and art spaces — and those of community members, neighborhoods and patrons.

Townsend will be expected to work with other organizations, including D.C. police, and the Transportation and Public Works departments, to address the types of problems that tend to arise after dark, according to Lindsey Parker, Bowser’s deputy chief of staff.

Other cities with an after-dark government official have gravitated toward former bar owners and nightlife personalities to run things.

Large cities including New York, London and Orlando, and even smaller ones such as Iowa City, have created such positions. They vary in title (night mayor, night czar, night manager) and responsibilities.

In her announcement, Bowser noted that Townsend would not be a “night mayor” as other cities have defined the role.

“You may have heard of some business about a ‘nighttime mayor,’ ” Bowser said. “I want to assure you, I am the nighttime mayor.”

D.C. Council member Brandon T. Todd (D-Ward 4) said he introduced the bill creating the nightlife office after seeing how the introduction of new bars, restaurants and businesses affected neighborhoods unprepared for the changes these new establishments brought — among them noise, traffic, congestion and drunk patrons.