Lake victim 'drawn into play fights with killers'

The decapitated body of 26-year-old Michael Gilbert was found in the privately owned Blue Lagoon in Arlesey, Bedfordshire, last May.

Brothers James Watt, 27 and Robert Watt, 20, of Chertsey Close, Luton, their parents and two other women are accused of killing him.

Giving evidence at Luton Crown Court, the men's brother, Colin Watt, 23, said he, Mr Gilbert and Robert Watt were filmed on a mobile phone hitting each other.

He told the court: "I thought it was funny at the time and so did the others, including Michael."

The jury heard last week how Mr Gilbert, who was described as a "vulnerable" man, was kept as a slave at the Watt family home and tortured for his benefit money before being killed.

Prosecutor Stuart Trimmer QC told the court Mr Gilbert was held captive and abused and assaulted for entertainment.

In his police statement, Colin Watt said the brothers and Mr Gilbert sometimes engaged in what they called "play fights", which involved kicking, head butting, elbowing, kneeing, and punching each other in the face.

He told the court Mr Gilbert, who first met James Watt at a children's home and later lived with his family at different addresses in Luton, regarded the Watts as his family.

A bag containing his headless corpse was found by two dog walkers on May 10, 2009.

It contained Mr Gilbert's torso, left forearm, hands, lower legs and feet.

The bag was weighted down with a stone from the patio wall at the Watt family home.

Mr Gilbert's head, which was only recovered last month, was also weighted down with another stone from the same wall.

Mr Trimmer has told the court Mr Gilbert was stabbed three times in the abdomen but that it was impossible to say exactly how he died because of the condition of the body.

James Watt denies murder and perverting the course of justice but has already pleaded guilty to familial homicide, the court has heard.

His brother Robert denies murder and familial homicide but has already pleaded guilty to perverting the course of justice.

Nichola Roberts, the girlfriend of a fourth brother called Richard Watt, and Natasha Oldfield, James Watt's girlfriend, both deny murder, familial homicide and perverting the course of justice. Oldfield is also charged with assisting an offender, which she denies.

The brothers' parents, Antonio Watt and Jennifer Smith-Dennis, deny familial homicide and perverting the course of justice.

Richard Watt, 25, has already pleaded guilty to familial homicide and perverting the course of justice.