Already convicted of murdering two other people, a Toronto man was also found guilty on Monday of murdering his father from whom he inherited a multimillion-dollar aviation business.

Dellen Millard “killed his father by shooting him in the left eye as he slept,” said Ontario Superior Court Justice Maureen Forestell in handing down her guilty verdict.

“I can find no theory consistent with innocence.” Wayne Millard, who was found dead in his bed on November 29, 2012 at the age of 71, ran a company called Millardair that he inherited from his father and which he transformed from a cargo carrier to an aircraft maintenance and servicing business.

Following his father’s death, Dellen Millard told police that the elder Millard was a depressed alcoholic stressed over the financial pressures the family business was facing.

During the trial Dellen Millard’s lawyer argued that Wayne Millard committed suicide, which police originally ruled was the cause of his death.

But police reopened the case after Mr Millard, now 33, and his friend, Mark Smich, were arrested and charged with the 2013 murder of Tim Bosma, a 32-year-old man whose truck Mr Millard and Mr Smich took for a test drive.

Mr Bosma was never seen again, and his truck was found on property owned by Mr Millard’s mother. Police believe Mr Bosma was shot and his body was burned.