Neville Lawrence, the father of murdered black teenager Stephen Lawrence has expressed concerns over government plans to abolish "double jeopardy".

The police and court's failure to secure a conviction for Stephen's suspected killers has been central to a campaign to change the "double jeopardy" rule so that those accused of his murder can be tried again.

"We have to be very careful when we start trying people over and over again for the same crime," he told GMTV's the Sunday programme.

His comments will be a blow to home secretary, David Blunkett, who is overseeing Labour's overhaul of the criminal justice system.

Moves to end double jeopardy and limit election for jury trial have provoked opposition from civil liberty campaigners, concerned that the reform could be misused by the police.

"If there are safeguards, which I don't know if they are, put in place to make sure that when you retry somebody you have really good fresh evidence and that you are not just leaving a person and then going back for them then I would be happy with that."

"But if it's just across-the-board when somebody is tried one time and you feel you've got enough to bring them back then I would be afraid of that happening because then it will be used for wrong purposes," he said.