The Copper Canyon Apartment Homes Shooting was a shooting on December 31, 2017, in Highlands Ranch, Colorado. One police deputy, Zackari Parrish, was fatally shot, and four others were wounded. Two civilians were also shot by the suspect, who was later killed in an exchange of gun fire with a SWAT tactical team. The suspect reportedly used a rifle and a shotgun. Law enforcement had responded first to a noise complaint, then to a domestic-disturbance call to the apartment. During the second visit, the suspect barricaded himself in his bedroom and shot the deputies in an "ambush" style when they entered. The suspect was later shot dead by a police tactical team that subsequently re-entered the apartment. It was later determined that the suspect, former attorney Matthew Riehl, was a veteran with a history of psychotic episodes and he had recently stopped taking his medication. Background Matthew Riehl Matthew Edward Riehl (September 9, 1980December 31, 2017) attended CU Denver, graduating magna cum laude in 2004, according to his mother. He had joined as an army reserve in 2003 before serving in the Iraq War as a combat medic whilst attending law school at the University of Wyoming, which he graduated from after returning from Iraq. He then went to work for a law firm in Rawlins, Wyoming for three years before leaving to set up his own practice. He joined the United States National Guard in 2006 reaching the rank of Specialist and serving from 2009 to 2010, again as a medic, in Kuwait and Iraq in the 300th Field Artillery Regiment where he didn't face combat. Riehl was involved in escorting convoys of troops through the desert at night. After being honourably discharged in 2012, Riehl developed mental health issues; in March 2014, his brother phoned the police for a welfare check on Matthew and he later went to hospital for treatment. In April, he was in a United States Department of Veterans Affairs (VA) mental health ward having experienced a psychotic episode before he escaped and was later found and brought back. On June 9, 2016, Lone Tree Police Department (LTPD) responded to an altercation between Riehl and his father. On June 8, 2017, LTPD again met with Riehl to conduct a welfare check; they talked for 14 minutes and claimed to have seen rifles in his basement, but had no reason to believe he was a danger