Leo Teskey was convicted in February 2008 of aggravated assault on Dougald Miller. (CBC)An Alberta judge has designated Leo Teskey, who has spent more than nine years in custody for a vicious attack, a dangerous offender.

Judge Eric Peterson ruled in Edmonton on Friday that Teskey, 40, meets the criteria to be designated a dangerous offender.

A vicious attack by Teskey in November 2000 left Dougald Miller, then a 61-year-old Edmonton apartment manager, bedridden and unable to speak or move.

Peterson said Teskey has a temper he cannot control, he is manipulative, has a substance-abuse problem and shows no remorse for his victims.

Teskey "is a serious threat to the safety of others," the judge said, adding that he "is willing to commit any type of crime to obtain personal gratification."

Teskey has 37 prior convictions, including one for assaulting a two-year-old boy and another for shooting a police officer in the head.

The dangerous offender designation carries an indefinite sentence that will keep Teskey behind bars until the National Parole Board is convinced he's no longer a threat.

Teskey was initially found guilty of aggravated assault in 2002 and declared a dangerous offender in 2005.

However, in June 2007, the Supreme Court of Canada overturned the aggravated assault conviction and the dangerous offender designation, and ordered a new trial, because the original judge took more than 11 months to deliver his written reasons for the verdict.

Lesley Miller seen in April 2010 tending to her husband Dougald. (CBC)Teskey was found guilty at a second trial in February 2008.

Outside court Friday, Dougald Miller's wife, Lesley Miller, said she's elated by the judge's ruling.

"But you know, I've got a message for Mr. Teskey. He picked the wrong victim this time," Miller said.

"He didn't realize that I would fight until the very end to get him put away. And when he goes to bed every night he'll think about us. And he won't harm anybody else."

Miller said she planned to head to the hospital to share the news with her husband.