The Supreme Court of Canada has thrown out the appeal of a man convicted of kidnapping Graham McMynn, the son of a wealthy Vancouver businessman.

Sam Tuan Vu was among five men charged in 2006 after McMynn, a UBC student and the son of weathy businessman, was grabbed at gunpoint from his car and held for eight days before he was rescued by police.

The judge, who tried the case without a jury, found Anh The Nguyen and Jose Hernandez guilty of both charges, while Sam Taun Vu was found guilty of unlawful confinement. Two other men charged were found not guilty.

The lower court's trial judge initially concluded there was no evidence Vu was involved when McMynn was moved between three different houses in the British Columbia's Lower Mainland — meaning he couldn't be found guilty of the kidnapping charge.

But the B.C. Appeal Court overturned the aquittal in 2011.The appeal court judges decided it was clear Vu was involved in holding McMynn against his will and knew full well he'd been kidnapped, making him a party to the kidnapping and guilty of that offence.

On Thursday in a unanimous decision, the Supreme Court upheld that decision.

Vu was originally sentenced to eight years, but the appeal court has ordered a new sentencing hearing because kidnapping carries a maximum sentence of life in prison — far greater than the 10-year maximum for unlawful confinement.