It's time for another trip into tmatt's personal GetReligion Guilt folder. Two weeks ago, the New York Times ran an article by Michael Moss and Souad Mekhennet that has haunted me ever since, especially since I read it just after returning from a trip to Istanbul. The leaders of religious minorities are still pretty tense there after the recent torture and murder of three Christians at a publishing company in Malatya.

Questions linger in the background, after events of this kind, hellish events that have almost become perfectly normal in Iraq.

Why do Islamists kill people like this? In this manner? On a doctrinal level, what are they thinking?

These are the questions at the heart of the Times article titled "Permission -- The Guidebook for Taking a Life." Ever since then, I have been trying to reach several of the Muslim researchers I met in Istanbul, seeking their commentary on this piece.

The bottom line: This is an amazing article. It is either amazingly good or amazingly bad, depending on whether it is dealing fairly with the source materials that it quotes. I do not know if I can make that judgment, to be honest with you.

If you read the lede you will not stop until the end:

We were in a small house in Zarqa, Jordan, trying to interview two heavily bearded Islamic militants about their distribution of recruitment videos when one of us asked one too many questions.

"He's American?" one of the militants growled. "Let's kidnap and kill him."

The room fell silent. But before anyone could act on this impulse, the rules of jihadi etiquette kicked in. You can't just slaughter a visitor, militants are taught by sympathetic Islamic scholars. You need permission from whoever arranges the meeting. And in this case, the arranger who helped us to meet this pair declined to sign off.

"He's my guest," Marwan Shehadeh, a Jordanian researcher, told the bearded men.

With Islamist violence brewing in various parts of the world, the set of rules that seek to guide and justify the killing that militants do is growing more complex.

This jihad etiquette is not written down, and for good reason. It varies as much in interpretation and practice as extremist groups vary in their goals. But the rules have some general themes that underlie actions ranging from the recent rash of suicide bombings in Algeria and Somalia, to the surge in beheadings and bombings by separatist Muslims in Thailand.

The article sets out to list the rules, as commonly understood by the small percentage of Muslims who interpret their scriptures to allow actions of this kind. Here is a list of the rules, as described in the Times article.

Rule No. 1: You can kill bystanders without feeling a lot of guilt.

Rule No. 2: You can kill children, too, without needing to feel distress.

Rule No. 3: Sometimes, you can single out civilians for killing; bankers are an example.

Rule No. 4: You cannot kill in the country where you reside unless you were born there.

Rule No. 5: You can lie or hide your religion if you do this for jihad.

Rule No. 6. You may need to ask your parents for their consent.

In each case, the reporters turn to mainstream Muslim scholars and to leaders in Islamist groups seeking input on the doctrinal debates that shape arguments about when and how people can be killed if they are viewed as enemies of Islam.

This is serious business and, like it or not, these debates are taking place within Islamic communities. As the article states:

Islamic militants who embrace violence may account for a minuscule fraction of Muslims in the world, but they lay claim to the breadth of Islamic teachings in their efforts to justify their actions. "No jihadi will do any action until he is certain this action is morally acceptable," says Dr. Mohammad al-Massari, a Saudi dissident who runs a leading jihad Internet forum, Tajdeed.net, in London, where he now lives.

And what do these debates sound like?

Consider Rule No. 4, which will continue to grow in importance in Europe and the United States in the years ahead. This is a long quote, but I want you to see what the reporters are doing and how they are doing it:

Militants living in a country that respects the rights of Muslims have something like a peace contract with the country, says Omar Bakri, a radical sheik who moved from London to Lebanon two years ago under pressure from British authorities.

Militants who go to Iraq get a pass as expeditionary warriors. And the Sept. 11, 2001, attacks did not violate this rule since the hijackers came from outside the United States, Mr. Bakri said.

"When I heard about the London bombings, I prayed that no bombers from Britain were involved," he said, fearing immigrants were responsible. As it turned out, the July 7, 2005, attack largely complied with this rule. Three of the four men who set off the bombs had been born in Britain; the fourth moved there from Jamaica as an infant.

Mr. Bakri says he does not condone violence against innocent people anywhere. But some of the several hundred young men who studied Islam with him say they have no such qualms.

"We have a voting system here in Britain, so anyone who is voting for Tony Blair is not a civilian and therefore would be a legitimate target," says Khalid Kelly, an Irish-born Islamic convert who says he studied with Mr. Bakri in London.

Like I said, I am sure there are many moderate and liberal Muslims who totally disagree with the interpretations featured in this article. That goes without saying.

However, in a way, that's the very point that Moss and Mekhennet are making. They are not trying to say that these are the official Muslim rules for taking lives. There are no official rules. They demonstrate that these are the rules being debated in some small sectors of Muslim communities, including here in the West.

And that is stunning enough. Please read and comment.