School Shooting At Robb Elementary In Uvalde, Texas
Days after the Uvalde school shooting, multiple schools across the country are receiving threats of shooting and terrorism. In photo: crosses with the names of victims of a school shooting, are pictured at a memorial outside Robb Elementary school, after a gunman killed nineteen children and two teachers, in Uvalde, Texas, U.S. May 26, 2022. Reuters / MARCO BELLO

Mass school shootings, like the one that killed 21 people last week in an Uvalde, Texas elementary school, have frequently led to litigation against school officials, law enforcement, perpetrators' families and gun manufacturers.

Outcomes of past cases have varied widely, with some cases dismissed on legal grounds early in litigation and others reaching settlement. No cases have so far been filed over the Uvalde shooting. Here is some of the notable litigation filed in the wake of shootings:

Columbine High School, Columbine, Colorado, 1999 -

Students Eric Harris and Dylan Klebold killed 13, including one teacher, and wounded 24. The massacre led to a slew of lawsuits against local officials, nearly all of which were dismissed on government immunity grounds. However, one lawsuit brought against police by the daughter of the slain teacher, accusing the police of refusing to allow paramedics to reach her father even after they knew the shooters were dead, was allowed to proceed and eventually settled for $1.5 million. Victims' families also reached a $2.5 million settlement with the families of the shooters and two other individuals who allegedly helped them obtain guns.

Red Lake Senior High School, Red Lake Indian Reservation Minnesota, 2005 -

Former student Jeff Weise killed seven people and wounded several others. Victims' families ultimately obtained a $1 million settlement with the school district and a $1.5 million settlement with a company that was tasked with developing a crisis plan for the school.

Virginia Tech University, Blacksburg, Virginia, 2007 - Student Seung-Hui Cho killed 32 and wounded 23. Some victims' families sued the school, but the Virginia Supreme Court ruled in October 2013 that the school was not liable because it did not have a legal duty to warn students of actions by third parties.

Sandy Hook Elementary School, Newtown, Connecticut, 2012 - Adam Lanza shot and killed 26 people, six staff and 20 six- and seven-year old children. Families of five of the children and four adults sued Remington Arms, maker of the Bushmaster AR-15 rifle Lanza used, and obtained a landmark $73 million settlement. The deal marked the first time a gunmaker has agreed to a major settlement over a mass shooting in the United States.

Marjorie Stoneman Douglas High School, Parkland, Florida, 2018 -

Former student Nikolas Cruz killed 17, three staff and 14 students, and wounded 17 others. A sheriff's deputy assigned to work at the school at the time, Scot Peterson, was heavily criticized for remaining outside during the shooting and was ultimately charged with child neglect, for which he is scheduled to stand trial later this year. While a federal judge dismissed negligence claims against Peterson and local officials, similar claims were allowed to proceed in state court and remain pending.

Santa Fe High School, Santa Fe, Texas, 2018 -

Student Dimitrios Pagourtzis killed 10 and injured 13 using a shotgun and a revolver. Two victims' parents sued Pagourtzis' parents, accusing them of failing to secure the weapons. Several victims' families also sued online ammunition retailer Luckygunner.com for allegedly selling ammunition to Pagourtzis without verifying his age. Both cases are currently pending.