On February 14, 2018, 19-year-old Nikolas Cruz opened fire on students and staff at Marjory Stoneman Douglas High School in the Miami suburban town of Parkland, Florida, United States, killing 17 people and injuring 17 others. Cruz, a former student at the school, fled the scene on foot by blending in with other students and was arrested without incident approximately one hour and twenty minutes later in nearby Coral Springs. Police and prosecutors investigated "a pattern of disciplinary issues and unnerving behavior".The incident is the deadliest mass shooting at a high school in U.S. history. The shooting came at a period of heightened public support for gun control that followed mass shootings in Paradise, Nevada, and in Sutherland Springs, Texas, in October and November 2017.
Students at Parkland founded Never Again MSD, an advocacy group that lobbies for gun control. On March 9, Governor Rick Scott signed a bill that implemented new restrictions to Florida's gun laws and also allowed for the arming of teachers who were properly trained and the hiring of more school resource officers.The Broward County Sheriff's Office received widespread criticism for its handling of the police response, both for not following up on multiple warnings about Cruz despite a lengthy record of threatening behavior and for staying outside the school instead of immediately confronting him. This led to the resignations of several police officers who responded to the scene, and the removal of Sheriff Scott Israel. A commission appointed by then-Governor Scott to investigate the shooting condemned the police inaction and urged school districts across the state to adopt greater measures of security.On October 20, 2021, Cruz pleaded guilty to all charges and apologized for his crimes. The prosecution sought the death penalty, and a four-month death penalty trial was expected to commence in January 2022. After suffering numerous delays, in part due to the COVID-19 pandemic, the trial commenced on July 18, 2022. On October 13, 2022, a jury unanimously agreed that Cruz was eligible for the death penalty, but deadlocked on whether it should be imposed, resulting in a recommendation to sentence him to life imprisonment without the possibility of parole. On November 2, 2022, Cruz was sentenced to life without parole, in accordance with a Florida law requiring the court not to depart from the jury's recommendation. The unanimity required to impose the death penalty has since been overturned by a bill signed by Governor Ron DeSantis, partly as a result of Cruz's sentencing.