A Gold Coast man who is pursuing legal action over alleged police brutality has been left with a brain injury, his wife says.

Ray Currier, 50, made headlines early last year after a video emerged appearing to show the grandfather being punched in the head and knocked unconscious while being restrained by five officers outside a Surfers Paradise nightclub.

"Our GP had already suspected this (brain injury), but the neurologist confirmed it yesterday," his wife, Kris Currier, told the Gold Coast Bulletin.

"The biggest difference is when he can look at you and not even know your name."

Mrs Currier said her husband also suffers blinding headaches.

Mr Currier, a youth worker and Justice of the Peace, was charged with assault and obstructing police but those charges were dropped in November, prompting his decision to pursue legal action.

The Crime and Corruption Commission is investigating the police brutality complaint.

On Australia Day last year, police were called after Mr Currier's colleagues, who he had been dining with earlier that night, were refused re-entry to Melbas nightclub.

Tensions escalated, and Mr Currier said he was trying to move his colleagues and their wives away from the area when the assault occurred.