BAGHDAD, Iraq – Following a recent string of alleged atrocities by American troops against Iraqi civilians, leaders from across Iraq’s political spectrum called yesterday for a review of the American-drafted law that prevents prosecution of coalition forces in Iraqi courts.

Prime Minister al-Maliki told reporters during a visit to Kuwait, “The immunity given to members of coalition forces encouraged them to commit such crimes in cold blood.” He added, “That makes it necessary to review it.”

The demand could widen a burgeoning rift between American and Iraqi authorities over killings and other crimes allegedly carried out in recent months. Mr. Maliki, who said last month that excessive force by American troops was commonplace, also said Monday that the government would open its own investigation into allegations of rape and murder by American soldiers during a March attack on a family in Mahmoudiya.

A top American military spokesman told reporters during a briefing in Baghdad that investigations into the Mahmoudiya case and several others are “being pursued vigorously.”

“We will hold ourselves accountable for our actions,” Major General William Caldwell IV added, saying the crimes would be an aberration and that American forces have made many positive contributions.

The dispute centers on a rule with the force of law enacted two years ago by the American-led Coalition Provisional Authority, which governed Iraq after the fall of Saddam Hussein. Known as CPA Order 17, it stipulates that coalition forces, diplomatic personnel, and their contractors “shall be immune from the Iraqi legal process.” But challenges to the immunity order have gained momentum, beginning with the November killing of 24 civilians in Haditha, which came to light in March when Time magazine reported the incident.

In a rare unified stance by factional leaders, members of Iraq’s ethnic Kudish and Sunni Arab political blocs endorsed Mr. Maliki’s call to revisit the immunity issue.

“In the name of immunity a lot of crimes have occurred, whether it is foreign forces or the security guards they have,” a Kurdish lawmaker, Mahmoud Othman, said.

Alaa Makky, an official with the Iraqi Islamic Party, the country’s largest Sunni Arab political group, said his organization has long criticized the immunity policy. While American forces will investigate certain “high-profile” cases, such as those in Mahmoudiya and Haditha, he said, “there are thousands of these events, really, that are vile and that never get noticed.”

An Iraqi government official, who spoke on the condition that he not be named, said Mr. Maliki hoped to revise Order 17 when the United Nations resolution authorizing the presence of American forces in Iraq is up for renewal at the end of the year.

General Caldwell called the immunity question a legal matter and said he would consult military lawyers before articulating a position. However, he appeared to leave room for negotiation on the issue.

“We are here as guests of the Iraqi government. They’re a sovereign nation,” General Caldwell said. “We’re going to sit and discuss with them whatever they want to discuss.”

But allowing Iraqi authorities to try American troops, who unlike contractors are subject to military courts-martial when accused of crimes, would be an unlikely, if not unprecedented, concession, legal experts said.

Immunity from prosecution is a common stipulation when American forces are sent abroad. The Bush administration has declined to join the International Criminal Court at the Hague, in part out of concern that American forces could be prosecuted for actions committed during foreign deployments. And a law passed by Congress in 2002 restricts American involvement in U.N. peacekeeping missions unless American forces are deemed immune from prosecution.

An international criminal law specialist at Vanderbilt University, Allison Danner, said that while America occasionally has allowed foreign governments to prosecute American troops, including in the Philippines and Japan, such decisions were made on a case-by-case basis, leaving the immunity intact.

“I can’t see them allowing the Iraqi government to decide when that should happen,” she said.

The case in Mahmoudiya, an insurgent stronghold south of Baghdad, has provoked a particularly strong reaction from Iraqi officials because of the attitude toward sexual crimes in Islamic culture. American soldiers are alleged to have raped a girl as young as 15 in her home, before fatally shooting her and three family members.

A federal prosecutor in North Carolina on Monday charged a former Army private first class, Steven Green, with rape and four counts of murder. At least four other American soldiers still in Iraq are under investigation.