After four years in business, Capitol Hemp is being forced to shut down its operation in Adams Morgan by police and prosecutors in D.C. The Capitol Hemp store has been the focus of investigations and raids by police. (Ricky Carioti/WASHINGTON POST)

Adam Eidinger stands next to the wall and gives it a good, solid knock.

“Hemp board,” he says. “First retail store to be built out of it. It’s held up remarkably well.”

Eidinger and business partner Alan Amsterdam imported 2,000 pounds of the stuff from China while building Capitol Hemp in an Adams Morgan basement four years ago. Since then, hemp-board shelves have held products also made of non-psychoactive strains of industrial cannabis — soap, paper, shoes, coats, hats. Dog beds and wood stain, even.

But no longer. Friday was Capitol Hemp’s last day of business.

The reason lies in the back of the store, behind a closed door. There, more hemp shelves held dozens of delicate glass pipes and other intricate smoking devices.

In October, D.C. police raided the shop and a Capitol Hemp location in Chinatown, now closed. They arrested six employees and seized $350,000 worth of glassware, alleging that its sale violated the city’s drug paraphernalia laws. To get their merchandise back and avoid criminal prosecution, Eidinger and Amsterdam agreed in April to close their D.C. shops.

On Friday, a steady crowd filed in for one last time to check out shirts and hats, many sporting images of cannabis leaves. Some inspected discount pieces of artisan glassware — don’t use the B-word — that retail for hundreds, sometimes thousands of dollars.

Its owners, meanwhile, stood in the shop commiserating with customers and soon-to-be-laid-off employees about doing business in a city where residents and elected officials have long supported medical marijuana and liberal politics, but police and prosecutors have taken a hard line on enforcing drug laws.

“We’ve been legal. We’ve paid our taxes. We’ve gotten all our permits,” Amsterdam said. “When you do everything by the book, you expect a little bit more.”

The shop now sells T-shirts with the words “Banned in D.C.” — a nod to the famed Bad Brains song. William Miller, a spokesman for the U.S. attorney’s office in the District, declined to comment on the shop’s prosecution.

When open, Capitol Hemp walked a fine line, promoting everyday uses of industrial hemp while selling items readily used for smoking marijuana and other artifacts of pot-smoking culture in a bright, cheery, patchouli-free environment. Its closing comes not long after Mayor Vincent C. Gray (D) personally hit the streets to take a hard line on drug paraphernalia. In July, he took a walking tour of Congress Heights to lobby convenience store clerks to stop selling rolling papers and “blunt” cigars.

Capitol Hemp doesn’t sell blunts, but it does sell tobacco and rolling papers in addition to the glassware. In the back room, restricted to those 18 and older, signs tell patrons “All Tobacco Accessories Intended for Legal Use Only” and “Do Not Make References to Anything Illegal or You Will Be Asked to Leave.”

While the merchandise might have raised the hackles of law enforcement, its neighbors in the bar-and-restaurant-packed area have few concerns about residing near “one of the top glass stores on the East Coast,” as Amsterdam calls the shop.

“I never heard any complaints about them,” said Kristen Barden, executive director of the Adams Morgan Partnership, a neighborhood business group. “I’ve heard from a couple of business owners that are really sad to to see them close. . . . We’ve had a hard time attracting retailers. Here’s an example of another retailer leaving.”

At the time of the raid, Capitol Hemp’s two locations employed 11. That’s now down to four. All of them, Eidinger said, were paid solid wages and health benefits.

Now Capitol Hemp is going Internet-only, and Amsterdam is scouting potential locations for a shop in the suburbs. Eidinger, whose criminal charges were dropped in August, is exploring other ideas for the basement space — a fallout-shelter-themed nightclub, perhaps — so far, to little avail.

Eidinger said he’s been “resigned for months,” left pondering the inanity of it all. “It’s really lame to walk away from a business that’s making money,” he said. “The city is just giving up $150,000 a year in tax revenue. It’s just giving it up. That’s dumb.”