There was a time when most people believed that honor killings – if they had even heard of them – took place far away, in places like Afghanistan and Algeria and Iran.

These days, we know otherwise. They happen here in the West as well: in Texas, in Toronto, in Paris and Amsterdam.

Now Phyllis Chesler, the pre-eminent authority on the phenomenon and author of the most comprehensive study on honor killings, has found something else we didn't know before: that many of these killings (and other honor violence) are perpetrated by women. "Women play a very active role in honor-based femicide," she writes in her latest report, "both by spreading the gossip underlying such murders and by acting as conspirator accomplices and/or hands-on killers in the honor killing of female relatives."

Chesler studied 31 honor killings from around the world in which women were identified as being either the killers or accomplices. According to her report, "Eighty-seven per-cent were Muslim-on-Muslim crimes; the remaining 13 percent were committed by Hindus, Sikhs, and Yazidis. Women were hands-on killers in 39 percent of these cases and served as conspirator-accomplices 61 percent of the time. In India, women were hands-on killers 100 percent of the time."

In an e-mail interview, Chesler, also the author of the award-winning memoir, An American Bride in Kabul, spoke about her findings and what they mean.

Abigail R. Esman, the author, most recently, of Radical State: How Jihad Is Winning Over Democracy in the West (Praeger, 2010), is a freelance writer based in New York and the Netherlands.