The members of an American family –– three mothers and six children –– killed in an ambush south of the border by a Mexican cartel were members of a community descended from a violent fundamentalist who believed in the doctrine of "blood atonement."
The nine victims were part of the LeBaron family, which has roots in the region dating back decades –– from the time Alma Dayer LeBaron settled in northern Mexico in 1924 and the remainder of his family was officially excommunicated by The Church of Jesus Christ of Latter-day Saints in the 1940s, according to author Ruth Wariner, a descendent of the family.
A number of fundamentalist Mormon communities moved south of the U.S.-Mexico border after the LDS Church barred polygamous marriages in 1890.
Anna LeBaron, granddaughter of Alma Dayer LeBaron, said none of the LeBaron family's dark past seems to be connected to Monday's killings. Mexican Security Secretary Alfonso Durazo has said it may have been a case of mistaken identity –– a drug cartel mistaking the convoy of large SUVs the family was traveling in for a rival gang, according to NBC News.
The LeBaron family founded the Church of the Firstborn, which soon split off into factions that viciously fought with each other following the patriarch's death. Alma's son Ervil LeBaron broke away from the rest of the family to found his Church of the First Born Lamb of God –– a sect driven by warped doctrines including the central belief in blood atonement, according to Wariner's account.
The tenet of blood atonement states that some acts like murder are unforgivable –– and the only way to offer atonement is to spill the blood of the offender on the ground as a sacrifice, according to resources from the digital collections at Brigham Young University.
The doctrine was reportedly the basis for capital punishment laws in Utah, which once sentenced convicts to execution by firing squad. (Notably, Utah's government passed a law in 2015 that once again allows convicts to be executed by firing squad if lethal injection is not an option, according to NPR.)
Ervil LeBaron used this doctrine as his motive for ordering the murder of his own brother Joel LeBaron –– Ruth Wariner's father –– in Mexico. Ervil was convicted for the crime in 1974, but his conviction was later overturned on a technicality –– and amid allegations of bribery, according to The Yucatan Times.
Ervil LeBaron's movement went on to kill at least 25 people throughout the southwestern United States during the 1970s according to The Los Angeles Times and Ruth Wariner's account.
Anna LeBaron said her father Ervil was dubbed "the Mormon Manson" for ordering mob-styled hits against his rivals or against people who left his cult movement.
Ervil had 13 wives and more than 50 children, including Anna LaBaron.
"We were taught that we were celestial children, having been born from the prophet Ervil LeBaron. And we believed it. Even though we were treated so poorly we still believed we were celestial children," she told BBC News in 2017.
Ervil died in prison in 1981 while serving a life sentence for the murder of a rival polygamist in 1977.
"It wasn't until after he died that it kind of started to break up and that power was lost," Anna LeBaron said. "However, even from the grave, he was able to control people and their actions and that is just mind-blowing –– that from the grave he was able to do that."
After Ervil's death, the cult began to break apart but violence continued well into the 1990s. The violence was abetted by Ervil's disciples drawing on a hit list of 50 people he regarded as traitors, hidden in a final theological tract known as "The Book of the New Covenants," according to the BBC.
Several members of Ervil's group were arrested in the 1980s and 1990s, including his sons Haber LeBaron Douglas Barlow, and Aaron LeBaron. Aaron LeBaron was sentenced to 45 years in prison for orchestrating a series of four killings in Texas in 1988, now known as the "4 O'Clock Murders," according to the Associated Press. The last person linked to the killings was sentenced to prison in 2011, according to a news release at the time from the Houston division of the FBI.
The LDS Church had disavowed Ervil LeBaron's movement decades ago, but expressed sadness about the Monday killings in a statement.
"We are heartbroken to hear of the tragedy that has touched these families in Mexico. Though it is our understanding that they are not members of The Church of Jesus Christ of Latter-day Saints, our love, prayers and sympathies are with them as they mourn and remember their loved ones," a spokesman for the current LDS Church told NBC News.
The family itself has largely worked to shed its dark past. Most members of the extended family no longer practice polygamy and the family today includes Catholics and people who are not religious, according to The Los Angeles Times.
But this is not the first time violence from the cartels in Mexico has visited the LeBaron family. In 2009, family member and activist Benjamin LeBaron was shot to death after speaking out against traffickers who had kidnapped his brother for ransom, according to The Los Angeles Times.
The extended LeBaron family has spoken out for years against drug cartel violence in Mexico and in support of looser gun laws, saying the family members need to protect themselves. The region where the attack took place Monday is disputed by two criminal groups, the Sinaloa cartel and a group linked to the Juarez cartel.
Mexican authorities have arrested a suspect they believe is connected to the brutal massacre. The unidentified suspect was allegedly found heavily armed and holding two hostages who were bound and gagged in a vehicle.
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