The city of Duluth won another round in its ongoing battle to keep a notorious downtown head shop out of business.

On Monday, the Minnesota Court of Appeals upheld the injunctions that shut down the Last Place on Earth, whose owner openly sold banned forms of synthetic drugs.

Store owner James Carlson was convicted of 51 felony counts stemming from his synthetic drug businesses and is currently in prison and awaiting sentencing.

In the year since Duluth secured a court order to close Last Place on Earth, city officials say crime and emergency calls have declined sharply. It's a far cry from the days when customers would line up down the block to get into the last store in the state that still sold products like synthetic marijuana and bath salts.

"It's been great for downtown. It's amazing how much has changed in just a year," said Duluth City Attorney Gunnar Johnson. "What was a real scourge on the city, on our business community, on our public safety – the police department, the fire department, the hospitals – has been lifted."

In the first 23 days after Last Place on Earth closed, the city saw an almost 44 percent drop in emergency calls to the neighborhood.

At Carlson's trial, emergency room physicians from St Luke's hospital testified that they went from seeing at least one synthetic drug overdose case per shift – raving, screaming patients who sometimes had to be placed into induced comas until the drugs left their system – to seeing none, said assistance city attorney Nathan LaCoursiere.

"It's like night and day. It's like the lights were turned back on" in downtown Duluth since the shop closed, La Coursiere said.

In his appeal, Carlson's attorney Randall Tigue argued unsuccessfully that the city's local ban on synthetic drugs was unconstitutional and the public nuisance charges against were unfounded. The appellate court affirmed the district court's permanent injunction against the business.

Tigue has not yet responded to a call for comment, but the Associated Press reports that Carlson plans to appeal.