A financial adviser accused of killing his disabled client with a bomb disguised as a Christmas present has been found guilty of first-degree murder in a Red Deer courtroom.

Brian Malley, 57, was charged in connection to the death of 23-year old Victoria Shachtay back in 2011.

The single mother died instantly when a parcel that looked like a Christmas gift exploded after it was delivered to her Innisfail home.

Shachtay was involved in a car crash in 2004 that left her a quadriplegic and had won a settlement for $575,000.

She asked Malley to help her invest the money and prosecutors told the court during his trial that he lost Shachtay's money and had resorted to paying her back out of his own pocket. They alleged that he wanted her dead to cut his losses.

Crown prosecutor Anders Quist reminded the jury that although some of the money was lost due to drops in the market, Malley also put some of her funds in high-risk investments.

He said Malley had called Shachtay "a pain in the ass" and described her as stubborn and lazy because she spent too much money and wouldn't get a job.

The defence argued that Malley didn't have the motive or expertise to carry out the killing.

"There's an easier way to cut your losses -- you just stop paying," defence lawyer Bob Aloneissi told the jury in his closing address. "Mr. Malley is being prosecuted because he cares for people, in this case, a single mom in a wheelchair."

A jury found Malley guilty of first-degree murder on Tuesday evening.

Malley was sentenced to life in prison with no chance of parole for 25 years.

(With files from The Canadian Press)