Ian Bush has been found guilty of the attempted murder of an elderly war veteran who was assaulted in his home in Ottawa.

Ernest Côté, a ​101-year-old veteran of the Second World War, was tied up and robbed inside his apartment building in New Edinburgh in December 2014.

Bush, claiming to be a City of Ottawa employee, had forced his way into the apartment.

He then tied Côté up and put a bag over his head, searched the apartment and fled with cash and undisclosed items.

Côté was eventually able to free himself and call police. He suffered only minor injuries and did not need to be taken to hospital.

He died in February 2015.

On Friday Bush was convicted of:

Attempted murder.

Robbery.

Forcible confinement.

Possession of a prohibited firearm.

Possession of a firearm.

Bush had his arms folded in front of him as the verdict was read.

"The verdict was just and fair. There was overwhelming evidence against Ian Bush on this charge. This is the proper, right and fair verdict," said Crown attorney James Cavanaugh.

Bush was smiling as he left the court room.

Côté's daughter expressed her relief at the verdict, and her gratitude to her now-deceased father.

"Dad was always a man of duty," Lucie Côté said. "He got [attacked], he got out of it, and it led to this denouement … especially for the Garon Family, [it was] important to solve that horrendous crime."

Convicted in 2007 triple murder

Earlier this year, Bush was also convicted of a "brutal, gratuitous" triple murder in 2007.

The victims, all in their 70s, were found dead in the living room of a luxury apartment.

Raymonde Garon, her husband, Alban Garon, and their friend and neighbour Marie-Claire Beniskos had been tied up and suffocated with plastic bags. The court heard the motive stemmed from a tax dispute when Alban was serving as chief justice of the Tax Court of Canada.

In the 1990s, Bush was battling Revenue Canada. The case finally made its way to the Tax Court of Canada in 1997, and a hearing was eventually scheduled for January 2001.

Bush told the Tax Court he was unavailable that day for "business reasons," but the court denied his request to set a new date.

It was Garon who made that decision, Bush's trial heard.

Bush sent odd documents to Garon, until Jun 2007 when he killed the three.

Murders unsolved for years

The murders would remain unsolved for years, until Bush assaulted Côté.

After Bush's arrest in December 2014, police searched his home and found a satchel in the basement containing ropes, plastic bags, knives, a sawed-off shotgun and other items.

Police used DNA evidence to link Bush to the murders of Beniskos and the Garons.

Bush received three automatic life sentences, to be served simultaneously, and will spend 25 years in prison before he's eligible for parole. By then, he'll be in his 80s.

He has yet to be sentenced for the attempted murder of Côté.

Bush will be back in court for sentencing on Dec. 18, three years to the date of his attack on Côté.