UNITED NATIONS, Nov 19 (Reuters) - A U.N. panel has rebuked Iran for an askew system of justice that too often used torture, amputation, stoning and other forms of "cruel, inhuman and degrading punishment."

The General Assembly's social, humanitarian and cultural committee on Thursday approved a critical resolution by a vote of 60 in favour, 41 against with 53 countries abstaining.

Adoption of the resolution by the committee, comprised of all U.N. members, is tantamount to formal passage in the General Assembly by the end of the year. The assembly a year ago voted in favour of a similar measure.

The resolution said Iran had made considerable progress in holding open debates, conducting fair local elections and opening investigations of those who abducted or killed intellectuals and student activists.

But it expressed "serious concern" at executions, torture, cruel, inhuman or degrading punishment and the "absence of due process of law."

The resolution also expressed concern at the restrictions of freedom of expression, opinion and at "interference with the work of writers and journalists and closure of publications."

And the document worried that student demonstrators might be sentenced to death and called on Iran to ensure capital punishment would not be imposed.

In July, authorities closed a reformist newspaper, setting off student-led protests that then led to an attack on a dormitory by vigilantes in which at least three people died and 1,200 were arrested. The thugs were said to be aligned with conservative politicians.

The paper's editor, Mashallah Shamsolvaezin, was released from jail on bail on Wednesday while awaiting the verdict of his trial on charges of insulting Islam.

New this year is a provision calling on Iran to ensure a "fair and transparent trial" for 13 Iranian Jews, including a rabbi and a 16- year-old boy, arrested in March on charges of spying for Israel.

And the committee's resolution again noted the "unabated pattern of persecution" including death sentences against the Baha'i, the country's largest religious minority, whose members are regarded as heretics by Iran.

The resolution was based on a report from Maurice Copithorne, a special investigator for the U.N. Commission on Human Rights, who said that while Iran had made some progress in human rights, events of the last year revealed setbacks.

His report said that Iran from January to mid-August had seen "more political and social turmoil than in recent years," with 138 people executed and prisoners tortured.

"The protection and promotion of human rights has had a central role in the recent turmoil, and the human rights of the participants and bystanders have been in jeopardy," said Copithorne, who has not been able to visit Iran.

He said that a commitment to reform by Iran's president, Mohammad Khatami, appeared undiminished "but the slow rate of implementation is leading to increased scepticism."

Iranian envoy, Mohammad Hasan Fadaifard, told the committee the report expressed "unfounded scepticism" on government policies but that there was also a national frustration with setbacks to Khatami's promised reforms.

He noted that police officers had been relieved of duties because of actions during the student demonstrations and criminal charges had been brought against some of them.

But he said the criticism against Iran's arrest of the 13 Jews was part of a politically-motivated "disinformation campaign" as non-Jews had also been arrested with them on the same charges.