Steven Simpson, 25, and Corryn Simpson, 26, were arrested over the July 25 shooting that killed Andrew Bott after a driving altercation in Littleton.
A 10:28 p.m. 911 call shows the couple reporting that a blue Ford truck hit their white BMW and fled, but they kept following the truck after dispatch told them to stop.
Steven is heard making a threat on the call before two gunshots, while the truck's driver separately told 911 that shots hit the vehicle and struck Bott in the head.
Bott was taken from the Columbine High School parking lot to a hospital, where he died; Steven is jailed on first-degree murder and Corryn on accessory charges.