A "vulnerable" man was kept as a slave and tortured for his benefit money before being killed and his headless body dumped in a lake, a court heard today.
James Watt, 27, of Chertsey Close, Luton, three other members of his family and two other women are accused of killing 26-year-old Michael Gilbert, whose decapitated body was found in the Blue Lagoon in Arlesey, Bedfordshire, last May.
Prosecutor Stuart Trimmer QC told Luton Crown Court that Mr Gilbert was held captive at the Watt family home and all six people charged bore some responsibility for what happened to him there.
He said: "He was kept as a slave at the address of the Watt family.
"He was kept, amongst other things, to take his benefit money."
Mr Trimmer said family members beat Mr Gilbert and filmed the beatings on mobile phones.
He said: "He was abused and assaulted in reality for entertainment.
"He was burnt, beaten, his body still had airgun pellets in it when it was taken from the lake."
The court heard that Mr Gilbert first met James Watt at a children's home when they were 15 and later lived with his family at a series of different addresses in Luton.
The family, including James's brother, Robert, 20, their father, Antonio, 60, and mother, Jennifer Smith-Dennis, 58, all treated him as a slave.
They were regularly joined by Nichola Roberts, 21, the girlfriend of another brother, Richard, and James's girlfriend, Natasha Oldfield, 29.
Mr Trimmer said they took Mr Gilbert's benefit money for themselves and forced him to work as their slave.
He said: "He was a vulnerable adult. He was homeless for some part of his life.
"He was estranged from his own family."
In January 2002, Mr Gilbert fled the Watt family and lived on the streets but they found him and forced him to come back.
Mr Trimmer said that, from that moment, he was "back under the control" of the family.
"His time in the Watt family household was marked by increasing violence," he said.
"Serious violence and humiliation."
Mr Trimmer told the court Mr Gilbert was hit with bats, shot, stabbed and made to walk around the house in only his boxer shorts.
He was forced to do chores and subjected to increasingly bizarre attacks.
On one occasion, he was made to goad a large pet lizard kept by the family until it attacked him with its tail.
Mr Gilbert escaped on two further occasions but members of the Watt family travelled to Cambridge and Blackburn to bring him back.
The court heard that James Watt would pose as Mr Gilbert and, using his National Insurance number, discover where he was collecting benefits.
On June 29 2007, Mr Gilbert was abducted from outside a JobCentre in Cambridge.
A month later, he and James Watt were arrested in Luton.
Mr Gilbert told police about the abduction but refused to press charges.
Mr Trimmer said: "He refused to support a police complaint saying this: 'It will make it worse for me in the long run'."
In September 2007, Mr Gilbert escaped to Blackburn but James Watt, who was described as being "obsessed" with tracking him down, found him and he was once more abducted, again from outside a job centre, on January 28 2008.
Mr Gilbert was again regularly beaten and humiliated in the months leading up to his death.
He was made to lie on the floor while people jumped on his stomach with both feet and James Watt regularly threw a snooker ball at him, the court was told.
He was made to sleep on the floor by James's bed and often handcuffed.
One witness said they saw Natasha Oldfield hit him in the stomach with a hammer repeatedly.
Mr Trimmer said: "From November to January, Michael was assaulted in one way or another every day."
One example of the "casual and random violence" he suffered was found in Natasha Oldfield's diary, which included plans for a game show where contestants would pay £5 to slap Mr Gilbert and £25 to headbutt him.
Mr Gilbert was killed some time between January 21 and 22 last year.
Mr Trimmer said: "On January 16, Michael Gilbert was seen by a member of JobCentre staff, alive.
"By the 22nd he was in parts in the lake. He died in that household and those in that household, the Crown says, are responsible.
"Each defendant, the Crown says, could and should have protected Michael."
A bag containing his headless corpse was found by two dog walkers on May 10 2009. One of them told police the bag had "the smell of death".
It contained Mr Gilbert's torso, left forearm, both hands, his 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 this month, was also weighted down with another stone from the same wall.
James Watt denies murder and perverting the course of justice. The jury heard he has already pleaded guilty to familial homicide.
His brother Robert denies charges of murder and familial homicide but he has already pleaded guilty to perverting the course of justice, the court heard.
Nichola Roberts and Natasha Oldfield both deny murder, familial homicide and perverting the course of justice. Oldfield is also charged with assisting an offender, which she denies.
Antonio Watt and Jennifer Smith-Dennis both deny familial homicide and perverting the course of justice.
A third son, Richard Watt, 25, has already pleaded guilty to familial homicide and perverting the course of justice. He will be sentenced after the trial.
Mr Trimmer told the jury that familial homicide was introduced into law in the last few years and allowed more than one member of a household to be charged over a death if evidence showed they could have done something to prevent it.