Reclusive billionaire James Packer will be grilled by the West Australian royal commission into Crown Resorts this week on his influence over the company and as the driving force behind the company’s catastrophic Chinese high-roller junket program.

Mr Packer’s first public appearance in more than a year comes as a six-week trial against Crown kicks off in the Federal Court on Monday, lodged by shareholders amid the fallout of the arrests of 19 Crown staff in China for illegally promoting and recruiting high rollers to gamble at its Australian casinos.