Virginia put to death a 41-year-old woman Thursday night, the first execution of a female in the country in five years and the first in that state for nearly a century.

The Rev. Lynn Litchfield, left, hugs a friend outside Greensville Correctional Center in Jarratt, Va., after the execution of Teresa Lewis on Thursday. (Steve Helber / Associated Press / September 23, 2010)

The lethal-injection death of Teresa Lewis, convicted of the 2002 contract killing of her husband and stepson, broke with a tradition of societal "queasiness" about executing women, one legal expert said. It could also psychologically clear the way to carrying out death sentences on others among the 60 condemned women in the nation - including 18 in California, according to some capital punishment observers.

Lewis' death sentence was only the 12th carried out against a woman prisoner in the 34 years since capital punishment was restored as a sentencing option. In that same period, 1,214 men have been put to death.

Legal scholars attribute the "gender bias" in executions to women's lower propensity to kill and the tendency of those who do to kill a husband, lover or child in the heat of emotion, seldom with the "aggravating factors" states require for a death sentence. Lewis pleaded guilty to having arranged the killings to collect $250,000 in insurance money on her stepson.

"The way capital punishment statutes are written inadvertently favor women. They make it a worse crime if a homicide is committed during a felony, like robbery or rape, which are rarely involved in women's homicides," said Victor Streib, a Northern Ohio University law professor who has spent 30 years researching condemned women. "It's also easier to convince a jury that women suffer emotional distress or other emotional problems more than men."

Still, Streib added, "there are some cases that can't be explained by anything except a queasiness at executing women. We just seem to be reluctant to do that."

Lewis was the first woman to be executed in Virginia since 1912, when a 17-year-old African American maid named Virginia Christian was sent to the electric chair for killing her employer after being accused of stealing a locket.

Lewis was the only woman on death row in a state that is second in the number of executions since 1976, with 107 compared with Texas' 463.

Texas carried out the last female execution in the United States on Sept. 14, 2005. Frances Newton was put to death by lethal injection for the murders of her husband and two children. Prosecutors said she wanted to collect $100,000 in insurance money.

A British national convicted in Texas of hiring men to kill a neighbor and steal the victim's newborn son also is likely to face execution this year. The U.S. Supreme Court has denied review of the conviction of 51-year-old Linda Carty, despite appeals by the British government to spare her life.

California has the nation's largest death row, with 708 condemned inmates. Nationally, there were 61 condemned women at the start of this year, compared with more than 3,200 men, according to the Death Penalty Information Center database.

University of New Mexico law professor Elizabeth Rapaport explains the death-sentence disparity with the kinds of crimes women tend to commit.

"Two thirds of the homicide crimes by women are domestic," she said, usually committed in the heat of argument or under impairment by drugs or alcohol, seldom with the premeditation or other aggravating circumstances that draw capital charges.

Rapaport said she was perplexed by the social perception that killing an intimate is less heinous than killing a stranger.

"Why do we reserve our greatest penalties for crimes against strangers, rather than those who violate the trust of the heart?" she asked. One reason, she speculated, is that murder in the course of kidnapping, rape or robbery induces fear of the unforeseeable, while few people read of spouses killing each other and think it could happen to them.

Most of the women on the nation's death rows are there because they committed the heinous crimes for which the death penalty was intended, Rapaport said.

"Is there some bias in the system? Might there be a prosecutor or a jury from time to time less inclined to prosecute a woman or convict a woman? I can't rule that out," she said. "But if someone wants to argue that a systematic preference exists, they have to get beyond hunch and anecdote and show me the money."

Even the comparatively few women on death row tend to be convicted of crimes against family and others they know.

California's condemned women include Dora Buenrostro, a Riverside women who stabbed her three children to death in a rage after a fight with her ex-husband. Susan Eubanks was sentenced to die by a San Diego judge for the 1997 shooting deaths of her four sons, and Sandi Dawn Nieves was convicted of setting fire to her Santa Clarita home in 1998, killing her four daughters to prevent their father from gaining custody. Mary Samuels, Catherine Thompson and Angelina Rodriguez, all of Los Angeles, received death sentences for the aggravated murders of their husbands.

State officials have been gearing up to resume executions after a nearly five-year hiatus, perhaps as soon as Wednesday. However, none of the women on death row have exhausted their appeals.