The Japanese 25-year-old, who finished third in the men's halfpipe at the 2014 Winter Olympic Games, was found guilty of causing a car collision that injured six people in September 2019. 

According to the ruling, Hiraoka hit a car while driving under the influence of alcohol in Katsuragi and fled the scene, The Mainichi Shimbun newspaper reported.

The Katsuragi branch of the Nara District Court sentenced Hiraoka to 30 months in prison, suspended for four years, with Judge Tetsuya Okuda calling the athlete's motives "extremely selfish".

Okuda handed Hiraoka a suspended sentence after claiming the snowboarder had shown remorse and had already been punished through a loss of sponsorship deals. 

"You won a medal at the Olympics and delivered a lot of hope to people, but disappointed so many because of the incident," Okuda said. 

"There are many things only you can do, such as telling others about what you gained from your athletic experiences.

"We would like you to continue to be an icon and hero."

Hiraoka enjoyed success in the early stages of his career, claiming halfpipe bronze at the Innsbruck 2012 Winter Youth Olympic Games and a silver medal at the 2013 Snowboarding World Championships in Stoneham. 

He has struggled to maintain this form more recently, however, finishing 13th in the halfpipe at the Pyeongchang 2018 Winter Olympic Games.