Shawna Forde was born on December 6, 1967. She grew up in a challenging environment, which shaped her early life. Forde described herself in 2007 as someone who had worked various jobs. She was a promoter for a grunge rock band, a youth counselor, an aircraft factory worker, and a cosmetologist.

As a teenager, Forde had multiple run-ins with the law. She had several convictions for theft, burglary, and prostitution, leading her to spend time in juvenile facilities. Forde was married four times. In 1989, a male friend accused her of physically attacking him and threatening to harm herself with a knife. There were also times when she faced legal issues for theft.

In 2008, Forde made a claim that she had been a victim of a drug cartel, alleging sexual assault and a shooting incident. However, these claims were later disputed by her brother who suggested she had made up the story. The case was eventually closed due to a lack of evidence.

In 2007, Forde became active in vigilante groups. She joined the Minutemen Civil Defense Corps but was expelled later. Following her expulsion, she helped establish a new group called Minutemen American Defense (MAD), claiming to have several thousand members. However, reports indicated only a few members remained after her later arrests.

On May 30, 2009, Shawna Forde and her accomplices, Jason Eugene Bush and Albert Gaxiola, entered the home of Raul Flores Jr. and his daughter, Brisenia, in Arivaca, Arizona. They pretended to be officials searching for fugitives. Forde and her group hoped to find money and drugs to fund their vigilante group, the Minutemen American Defense. When they found nothing of value, they stole inexpensive jewelry instead.

During this home invasion, Raul Flores Jr., aged 29, and his nine-year-old daughter Brisenia Ylianna Flores were fatally shot. Gina Marie Gonzalez, the wife of Raul and mother of Brisenia, was also in the house at the time and sustained gunshot wounds. To survive, she pretended to be dead after being shot three times. After the attackers left, Gonzalez called 9-1-1.

While on the phone with the operator, the intruders returned, and Gina exchanged gunfire with them. In this confrontation, she managed to wound Bush in the leg. The attackers then fled the scene. Afterward, Gonzalez identified Forde and Bush, stating that Bush had killed her daughter and husband.

Later investigations found that Forde had jewelry belonging to Gonzalez when she was arrested. Evidence suggested that Forde had planned the crime for months and had recruited her accomplices for the attack.

In February 2011, all three attackers were convicted of murder. Forde and Bush received a death sentence, while Gaxiola was sentenced to life in prison without parole plus additional years.