By JUAN FORERO
 
BOGOTÁ, Colombia, Nov. 15 - A panel of legislators plans to present President Álvaro Uribe's government with a bill this week that would provide prison sentences of up to 10 years for any right-wing paramilitary fighters found guilty of atrocities and require them to return any ill-gotten gains, according to people who have worked on the proposed legislation.

The proposed penalties would form part of the government's conditions for a peace agreement with the United Self-Defense Forces, a right-wing militia financed by landowners and drug traffickers that emerged in the 1990's to combat the Marxist rebels who have fought against the government for the past four decades.

For months, Mr. Uribe's government has conducted talks with the militia aimed at disarming thousands of its fighters. Though illegal, the paramilitaries consider themselves allied with the state, using selective assassinations and mass killings to undermine the rebel forces.

But with their leaders facing murder charges here and drug trafficking charges in the United States, the paramilitaries have been pressing for an amnesty and protection from extradition in exchange for a complete demobilization of their 15,000 fighters by the end of 2005. The government is seeking a legislative framework for the peace talks because the existing penal code is deemed inadequate to deal with crimes committed during the years of civil conflict.

A bill proposed last year by President Uribe and backed by the Bush administration would have effectively granted immunity to the paramilitary leaders in exchange for laying down their arms.

But that plan prompted a chorus of criticism from foreign diplomats, the United Nations, human rights groups and some of Mr. Uribe's own allies, who said the plan would allow paramilitary commanders wanted for mass murder and cocaine trafficking to go free.

Now, as the paramilitaries prepare to follow through on an offer to demobilize 3,000 fighters later this month, the 25-page bill appears to be the legal framework Colombia's government has wanted to move forward in the talks. The proposal has the support of conservative allies of Mr. Uribe and key leftists in Congress like Wilson Borja, who was severely wounded in an assassination attempt orchestrated by paramilitaries.

"The most important thing about this law is that it has ample political support," said Senator Rafael Pardo, an influential supporter of Mr. Uribe who has spearheaded the drafting of the bill. "It's not being proposed by the opposition, or the government or some other sector."

The Uribe administration may propose changes later this week, but a final bill is expected to be presented to Congress next week. Passage is expected early next year, and the country's Constitutional Court would also have to give its approval.

The biggest impediment, though, is the 10-member paramilitary negotiating team.

In interviews last week in a swath of territory ceded to the paramilitaries for talks, one commander, Diego Fernando Murillo, who did not know details of the bill in Bogotá, was emphatically opposed to serving jail time.

"If someone says give up, turn in your arms and you'll spend 30 years in jail, well, we cannot do that," he said. "I always like to say, 'Let's not think of yesterday's dead.' "

Another commander, Rodrigo Tovar, carefully choosing his words, said he could accept punishment as long as there were "parameters of dignity." He would not say for how long he would go to jail, but said, "If you ask me, I could say I won't spend one year in jail, but it's not up to Rodrigo Tovar."

The paramilitaries also remain concerned about American requests for the extradition of several commanders for cocaine trafficking. The bill says nothing about extradition, though Mr. Uribe's government has signaled to the paramilitaries that it may be flexible on the matter.

Under the proposed law, militiamen from the United Self-Defense Forces of Colombia would admit their crimes, provide investigators with details of Colombia's vast paramilitary structure, compensate victims and turn in land and other belongings obtained illegally.

The bill would create a special unit of prosecutors to investigate crimes, and a special tribunal to hand down sentences.

Those paramilitary fighters deemed not to have committed crimes against humanity or other serious violations, like drug trafficking, would receive amnesty.

But top commanders would face at least eight years in jail, and possibly as many as 10. Others involved in serious crimes would probably face five years' imprisonment.

The bill asks that a special council be created to oversee reparations payments, which paramilitary commanders would be required to make to ensure their freedom after serving jail time. The victims of paramilitary violence would also take part in judicial proceedings, providing evidence if need be, and in the reparations process.

The paramilitaries may balk at some demands in the bill and at mechanisms to ensure that commanders abide. The group's leaders have publicly argued that they are not a scourge on Colombia but rather the country's saviors - having rid vast regions of leftist rebels by killing thousands of villagers accused of supporting insurgents.

"I ask, who is going to give me reparations?" said Mr. Tovar, who controls up to 5,000 men across northern Colombia.

Senator Pardo, though, says that if the law passes, the paramilitaries have no choice. They are already moving forward on disarmament, he said, and this may be their last chance.

"Since this is the only alternative, it has to be acceptable to them," Mr. Pardo said. "They have to accept."