Dad assaulted outside WA pub: trial

A father who had been celebrating his son's birthday was punched to the ground and then kicked as he lay motionless outside a pub, a Perth court has heard.

Gareth Jay Hitchcock and Calem Milburn-Thomas are on trial in the West Australian District Court accused of doing an act with intent to harm that endangered the health or safety of Glenn Macgregor Palmer.

In his opening address on Monday, prosecutor Justin Whalley said Mr Palmer, his son and some friends were waiting at a taxi rank outside Murphy's Irish Pub in Mandurah, south of Perth, in August 2014 when he was knocked to the ground by someone in the other group.

Mr Whalley alleged Milburn-Thomas then hit Mr Palmer while he was lying on the ground motionless and kicked him in the back.

Hitchcock also kicked the victim to the face, Mr Whalley said.

He told the jury they would be shown CCTV footage of the incident from different camera angles.

Mr Whalley said the intent to cause harm to Mr Palmer may have been fleeting and impulsive, and perhaps the accused men regretted their actions, but that was not the point.

Hitchcock's lawyer Jeremy Scudds said people standing outside the pub were upset because someone had been assaulted at the venue.

He said Hitchcock was trying to break things up when he was struck, and then kicked Mr Palmer to the chest - not the face - to get him to stay on the ground after he made threats.

The lawyer for Milburn-Thomas did not make an opening address.

The trial continues.