An Edmonton man — and not the police — should be able to keep $18,000 that he found in an envelope wrongly put in his mailbox, a judge has ruled.

An Alberta Court of Queen's Bench judge ruled last week that Burton Thomas should not only get the cash, but also the costs of his court case against Canada's Attorney General.

The police had been refusing to return the money, which Thomas found wrapped in 18 bags in an envelope in his post office box in July 2005.

After he opened it, he realized that it was addressed to another post office box at the same location as his. He photocopied the cash to have a record of it, then took it to the Edmonton police, who handed it over to RCMP.

The intended recipient of the envelope "refused to provide any explanation or acknowledgement of ownership of the money" when contacted by police, according to a written judgment from Justice Marguerite Trussler. No charges were laid.

Wanting the money back and unable to get it from police, Thomas sued the RCMP through the Attorney General of Canada.

Trussler ruled on Oct. 4 that Thomas legally took possession of the money when he opened the envelope.

The defence had argued that Thomas shouldn't be allowed to profit from a wrong —opening an envelope that didn't belong to him.

However,Trussler said there is no evidence to show that Thomas knew the envelope was for someone else when he opened it, and he did the right thing by turning it in to police.

"Thomas turned over the money to the RCMP with the intention of having it restored to the true owner. He did not intend to abandon the money or to surrender his rights to the possession of the money," the judge said.