A Duluth head-shop owner scheduled to stand trial in federal court this week for an alleged conspiracy to sell synthetic drugs was denied the return of his cash and guns seized during a raid two years ago.

Last Place on Earth owner Jim Carlson stands charged with 54 counts of illegally selling the products by allegedly “misbranding” them as herbal incense, bath salts, glass cleaner and other names. Jury selection begins Tuesday in Minneapolis.

Carlson’s appeal cited a raid on the store on Sept. 21, 2011, in which authorities seized weapons, cash, business records and suspected synthetic drugs.

A month later, Carlson filed a complaint against the city of Duluth, asking for the return of the weapons and $83,000 cash, arguing that the search violated his constitutional rights, and that police seized items not specifically referenced in the search warrant.

A St. Louis County judge ruled in February 2012 that the seized items were within the scope of the warrant and that police may retain them pending the outcome of Carlson’s criminal trial, and dismissed his claim without prejudice, meaning he could refile it again in the future.

Carlson appealed, but the appeals court sided against him, reasoning that the federal charges were directly related to the seized evidence.

Further, they wrote, Carlson’s civil rights weren’t violated because he can refile his claim down the road.

Carlson first drew attention from local authorities two years ago as a source of fake pot and other synthetic drugs in Minnesota, while the increasing popularity of the drugs alarmed authorities who blamed them for thousands of calls to poison control centers and dozens of deaths in the United States, including at least two in Minnesota.

Carlson, whose store is currently shuttered pending the outcome of a nuisance lawsuit brought against Carlson by the city of Duluth, has been an outspoken challenger of the government’s right to crack down on synthetic drugs, saying the laws used to prosecute sellers have been “unconstitutionally vague.” Carlson, who admittedly made millions of dollars, said his sales tripled after he began selling synthetic drugs in 2009.