In this artist's sketch, Douglas Garland appears in court in Calgary on Monday, July 7, 2014. Garland, who has been identified in local media as a person of interest in the disappearance of a Calgary five-year-old and his grandparents, made a brief court appearance charged with identity theft in an unrelated case.

Image Credit: THE CANADIAN PRESS/Janice Fletcher

CALGARY - A man identified as a person of interest in the mysterious disappearance of a Calgary child and his grandparents has been described in past court documents as an intelligent but troubled man.

Douglas Garland has been named in local media reports as the man police took into custody Saturday for questioning in the disappearance of five-year-old Nathan O'Brien and his grandparents Alvin and Kathy Liknes. They have been missing since June 29.

Police said the man was released Sunday, but is still a person of interest in their investigation.

However Garland, 54, remained in custody charged with identity theft in an unrelated case. He appeared in court briefly Monday on closed-circuit video and a judge adjourned the matter until a bail hearing Wednesday.

The balding man was dressed in a blue jumpsuit and told a judge he had not yet hired a lawyer.

Nathan's father, Rod O'Brien, was in court for the appearance. When asked if he knows of a connection between his family and Garland's, he said, "I do. But I'm not going to comment today."

Rod O'Brien appeared with his wife last week in front of cameras, tearfully urging for the return of his "superhero" son and the grandparents.

The boy had been at his grandparents' on a sleepover on the night of June 29 after the couple held an estate sale at their Calgary home on the weekend. They were selling their things as they prepared for a move to Mexico.

When his mother went to pick him up the next morning, no one was home. Police have said there is evidence a violent incident occurred in the house, but they still hope to find everyone alive. They have not disclosed a motive.

Officers continued Monday searching an acreage and surrounding property near Airdrie, a bedroom community north of Calgary, where Garland lived with his parents.

Court records say Garland served time in prison for making amphetamines at his parents' farm.

A federal tax court ruling from 2005 shows Garland once had a promising future.

He went to medical school for a year but left after having a mental breakdown, says the ruling. It says he was also traumatized after a horrific car crash caused when he fell asleep at the wheel and suffers from attention deficit disorder.

The document says after Mounties raided his parents' property in 1992, he was released on bail and fled to Vancouver, where it says he assumed the name of a deceased person named Matthew Kemper Hartley. A cemetery website lists a 14-year-old boy with the same name who was buried in southern Alberta in 1980.

The court document says Garland had enough science skills to get a job at a laboratory to test pesticides, herbicides and organic compounds. He was eventually promoted to supervisor but, after four years, suffered another breakdown and was fired from the job in 1997.

He later got a part-time job at the British Columbia Institute of Technology, but "the RCMP eventually caught up to Mr. Garland and he was arrested in May 1999."

Justice officials say Garland pleaded guilty to two counts of drug trafficking and was sentenced to 39 months. He received an additional one month for possession of stolen property.

After he was released, the Canada Revenue Agency went after him for employment insurance benefits it gave him when he left his laboratory job because he had been using a fake name and a fake social insurance number.

Garland took the agency to court and, acting as his own lawyer, won his case in 2005.

Justice Campbell Miller with the Tax Court of Canada ruled that Garland was smart and did his job well at the lab.

"While Mr. Garland assumed the name to avoid detection, he did not enter the employment agreement with any evil intention — he simply needed to work in a job for which he was qualified," wrote the judge.

"This troubled man should not be precluded from receiving benefits from a program into which he and his employer paid on the basis of the illegality of the contract."

Court records show Garland had no other problems with the law until a few years ago.

In January 2010, he received a $575 fine for failing to yield to a pedestrian in Airdrie.

News from © The Canadian Press, 2014