A series of clemency hearings for almost every prisoner facing the death penalty in the US state of Illinois has begun.

It has become apparent that our state's death penalty system is severely flawed

Charles Hoffman Lawyer

The cases of 142 murderers - convicted of killing around 250 people - will be reviewed with the possibility that the state's Governor George Ryan will commute all their sentences to life in prison.

Correspondents and analysts say the unprecedented nine days of hearings at the Prisoner Review Board effectively puts the death penalty itself on trial.

The review also highlights the powers of state governors to grant clemency unilaterally - often at the end of their terms.

Governor Ryan, who leaves office in January, was the first to declare a moratorium on executions three years ago after three murder convictions were overturned with new examinations of DNA evidence.

But 160 killers remain on death row in the state's prisons and 142 of them have now asked for mercy at the hearings which are held in Chicago and the state capital, Springfield.

Brutal crimes

The prisoners have been convicted of some of the most brutal crimes in the state. They include Leonard Kidd, who killed 10 people - including children - in an arson attack in 1980, and stabbed four others to death in 1984.

Governor Ryan halted executions in his state three years ago

During his hearing, lawyers argued that Kidd was mentally retarded, and that executing him constituted cruel and unusual punishment.

"It has become apparent that our state's death penalty system is severely flawed," said lawyer Charles Hoffman in a hearing for Kenneth Allen - who pleaded guilty to the 1979 killing of two Chicago policemen.

Ahead of the hearings, Anne Taylor, chairman of the review board, insisted that they would consider each case individually.

"Families, survivors and attorneys for all parties will have ample opportunity to present testimony before the board members," she said.

Dennis Culloden, a spokesman for Governor Ryan, stressed that it was up to the governor to take all the final decisions.

"All of the options are on the table - whether it's to deal with certain types of cases, whether it is to accept each recommendation or [to do] a blanket commutation," he told the Chicago Tribune newspaper.

Supporters of an end to executions hope that the mass hearings will generate new debate on the death penalty.

Rob Warden, director of the Center on Wrongful Convictions at Chicago's Northwestern University, told the New York Times: "Beyond the question of guilt or innocence, of course, is the question of proportionality and fairness of the sentencing process.

"Isn't it better that we let 10 absolutely guilty men who committed horrible crimes spend the rest of their lives in prison, rather than risk one, a single execution of an innocent person?"

Sentences 'deserved'

But Richard Devine, the state's attorney for Cook County which includes Chicago, told the same newspaper that the people on death row were "the worst of the worst" whose sentences followed proper deliberation and examination under the justice system.

Hearings will be held in Chicago, and the state capital Springfield

"Many of these individuals are the personification of evil," he said.

"They richly deserve the penalty they have received under due process of law."

The issue has become part of the election campaign to find a successor to Governor Ryan.

Jim Ryan, the Republican candidate and Illinois' attorney general who is unrelated to the governor, tried to stop the hearings but his lawsuit was dismissed.