Stan and Michael (foreground) Gregory continue with their case against the police. Photo / Jeff Brass

Stan and Michael (foreground) Gregory continue with their case against the police. Photo / Jeff Brass

Conflicting stories over the actions of a police officer who arrested and pepper sprayed an innocent man, have emerged as the matter comes before a court.

Six years ago police broke into Michael Gregory's home, emptied a can of pepper spray into his eyes, and arrested him for crimes he didn't commit. The charges were later dropped.

His father Stan has spent tens of thousands of dollars on civil proceedings against the officers to fight the "miscarriage of justice", because police refuse to lay criminal charges.

Now, documents obtained by the Herald on Sunday have revealed discrepancies in the story of the officer at the centre of the case.

Constable Thomas Gollan first said he had entered the house through a window, resulting in an altercation with Gregory and the use of the pepper spray. The police defence to the Gregorys' civil case now says Gregory resisted arrest at the window, so Gollan sprayed him.

According to a disciplinary report filed to the Police Complaints Authority, officers investigating a burglary in Papakura followed a police dog to Gregory's house in the early hours.

Gregory, who spoke to Gollan through his bedroom window, refused to open the front door without a search warrant or permission from his father - which he is entitled to do.

The disciplinary report said: "Constable Gollan has then entered the window, resulting in a verbal and then physical altercation between him and Michael Gregory, which then resulted in the use of OC spray."

Gregory was arrested on suspicion of aggravated assault, aggravated burglary, burglary, resisting arrest, obstruction of justice and assaulting a police officer. Nine weeks later the charges against the then 21-year-old were withdrawn and another man was charged - but only after his father Stan hired a private detective to investigate.

The disciplinary report concluded:

* The arrest of Michael Gregory was unlawful.

* Any physical evidence obtained at the scene was inadmissible in court.

* The use of OC spray was unnecessary.

* The detention of Gregory was unlawful.

The report criticised officers for a lack of leadership, and for not investigating the burglary professionally.