He also called for the establishment of a commission to review wrongful convictions in cases like those involving the four people in New York State whom the Innocence Project has helped exonerate in the last year through DNA testing.

Amnesty International said the lack of appeals gave "unfettered and unchallengeable discretionary power to the executive to decide who will be prosecuted and under what rules, as well as to review convictions and sentences."

The Court could review criminal convictions from the state courts, but not the lower federal courts, via writs of error.

But they differed markedly on how it affected the Supreme Court's authority to review convictions.

Two weeks ago the Court called for argument over whether Federal judges should give extra deference to state legal judgments, including erroneous ones, when reviewing criminal convictions for constitutional error.

An innocence commission is a legal commission set up by a government to review criminal convictions in a new light.

During the Rehnquist years, the court enhanced the police's ability to conduct searches and to have the search results introduced at trial; expanded police officers' immunity from lawsuits for constitutional violations; and cut back sharply on the role of the federal courts in reviewing state-court criminal convictions.

Generally, the Supreme Court reviews cases in which the lower court declares a state statute or state constitutional provision to be invalid, appeals involving the death sentence or convictions of over 20 years, said Lawrence Moore, director of communications for the State Judicial Department.

One provision would prevent federal courts from reviewing convictions in a large number of capital cases.

On 6 April a special working group of the Kyrgyz Supreme Court was formed to review Kulov's earlier prosecution and convictions, and by 11 April he had been cleared of all charges.