Ronald Lee Haskell Jr. was born on August 26, 1980. He grew up in San Marcos, California. His childhood included a period of living in Eagle River, Alaska, until 2004. Haskell attended Chugiak High School in Alaska and graduated in 1999. During his high school years, he was known for his lively personality and was voted class clown. He also earned the titles of prom king and homecoming king.

After finishing high school, Haskell worked as a parcel delivery driver for a company that had a contract with FedEx. He married Melannie Kaye Lyon on March 15, 2002, in Orange County, California. The couple moved to Logan, Utah, where they lived together from July 2006 until November 2013. They had four children during their marriage.

In 2008, Haskell faced charges related to domestic violence. He was accused of dragging his wife out of bed and hitting her, which he later downplayed by saying he had only pushed her. He pleaded guilty to a simple assault charge, and other charges were dismissed after a plea deal.

In the years following their marriage, Haskell and Lyon's relationship became increasingly troubled. She filed for divorce in August 2013, and a protective order was issued against Haskell because of a history of conflicts. After the divorce, Melannie gained primary custody of their children, while Haskell moved back in with his parents in San Marcos.

In July 2014, Haskell's relationship with his family continued to deteriorate. His mother sought a restraining order against him after a violent argument that escalated to threats against her life. 

On July 9, 2014, Ronald Lee Haskell Jr. went to a home in Harris County, Texas, dressed as a FedEx employee. He was looking for his ex-wife, who was related to the family living there. A 15-year-old girl answered the door, but she didn't recognize him. Haskell asked about her parents, and when she told him they were not home, he left. He returned shortly after and told her he was her ex-uncle. When she tried to shut the door, he forced his way inside.

Once inside, Haskell tied up the girl and made her lie face-down. He did the same to four other children and their parents when they returned home. Haskell demanded to know where his ex-wife was. When they did not provide the information, he shot all seven of them in the head. After this, he fled the scene using the family's car and fired his weapon 13 times inside the house.

Five of the victims died at the scene, while one child died later at the hospital. The only survivor was the 15-year-old girl, Cassidy Stay. She got shot but managed to survive by pretending to be dead. After the incident, she helped the police by identifying Haskell and informing them he was likely targeting more family members.

Using Cassidy's information, the police found Haskell's location. A chase occurred for about twenty minutes, involving numerous police cars. The chase ended in a cul-de-sac about three miles from the shooting site. Haskell was cornered and made a threatening gesture by holding a gun to his head. He negotiated with police via cellphone while nearby homes were evacuated. After several hours, he surrendered without further incident.

Haskell was charged with six counts of capital murder on July 10, 2014. During his first court appearance, he collapsed when the charges were read. He faced multiple court appearances and was found guilty of capital murder in September 2019. He was sentenced to death on October 11, 2019, and is currently on death row. A memorial service was held for the victims shortly after the tragedy.