LAHORE, PAKISTAN - An American effort to win freedom for a CIA security contractor jailed here has focused on an assertion that he is shielded by diplomatic immunity. But many here say that the release of the contractor, Raymond Davis, would also require a bow to a tradition enshrined in Islamic law: the payment of blood money.

To date, there has been no sign of progress in an impasse between the United States and Pakistan over whether Davis should stand trial in the killing of two Pakistanis more than a month ago. In Pakistan, protesters are vowing to riot if Davis is released, intelligence agents are threatening to limit cooperation with the CIA and some politicians are demanding something U.S. officials deem a non-starter - the release of a Pakistani woman convicted of trying to murder American military officers. U.S. officials maintain that Davis, who has claimed self-defense, has immunity and is being detained illegally.

But some senior government and police officials say they see a window of opportunity. In Pakistan, disputes over killings are regularly solved out of court as an agreement between the victims' heirs and those responsible for deaths. The former must forgive, and the latter must pay diyat, or compensation.

Prime Minister Yousaf Raza Gillani has suggested such a payment as one possible solution. In a recent interview, another senior Pakistani government official said that "the opinion of the government and many sensible people" is that the payment of money could prompt the families of those killed in the episode to drop their cases.

But this is a country seething with anti-American sentiment, and as with everything surrounding the case, the idea of compensatory payments has been divisive. Most prominently, religious groups - normally the champions of Islamic law - have taken to the streets to oppose compensation and scold the government for "pressuring" the relatives of the victims to accept it.

"This is not a case for compensation," said Liaqat Baloch, secretary general of the religious party Jamaat-e-Islamic, who spoke after a rally in Lahore where throngs of men called for Davis to be hanged. Baloch said that the families would not accept U.S. money and that "the people of Pakistan" would provide any funds they might need.

In interviews, relatives of the two men shot by Davis in a street altercation and a motorcyclist killed by a U.S. consulate vehicle that was rushing to Davis's rescue said they had not been approached by the Pakistani or U.S. governments. The relatives said that representatives from religious parties had been the only regular visitors and that their arguments against accepting compensation had been persuasive.

"We can't straightaway accept money and let it go," said Ijaz ur-Rehman, 39, the brother of the dead motorcyclist.

U.S. officials declined to say whether diyat is under discussion in the Davis case. A Pakistani newspaper reported Sunday that the U.S. Embassy in Islamabad has pursued the option at least twice, paying $10,000 to relatives of each of two men fatally struck by embassy cars in 2010. Alberto Rodriguez, an embassy spokesman, said only that "the embassy has acted responsibly whenever there have been incidents involving accidents with embassy employees."

The payment of compensation to settle killings is controversial among human rights activists and some lawyers in Pakistan. Critics argue that it allows those with money to kill with impunity and trivializes homicide as a personal, not societal, crime - objections that could complicate U.S. efforts to pursue payments.

But lawyers and police say the practice is common both in urban and rural areas, where such settlements can forestall or end lasting intertribal battles. Although the United States seems unlikely to take any step that looks like an admission of guilt, experts say public sentiment would demand some compensation be paid.

"From a Pakistani public opinion perspective, this is probably going to be the easiest way to get out of the logjam," said Babar Sattar, an attorney and newspaper columnist. "It is an Islamic principle that's been followed for centuries . . . if somebody wants to get away from the pain of dealing with something like this."

Of course, the families of the dead men must forgive in exchange for payment, and this they have not yet done.

Mokhtar Ahmed, 50, an uncle of Faizan Haider, one of the men fatally shot by Davis, said several people whose affiliations he did not know have visited the family and offered to mediate a settlement, insisting it is futile to battle the United States.

"But now we think we should not budge," he said.

"Blood for blood," said Wasim Shamshad, whose brother, Faheem, was also killed in the shooting. "Islam says whatever the crime is, the punishment should be the same."