D.C. police officer Richmond Phillips fatally shot his former mistress and then let their infant daughter “cook” in a car that had its windows rolled up on a hot spring day, Prince George’s County’s top prosecutor told a jury Monday.

Phillips’ trial in the deaths of Wynetta Wright, 20, and Jaylin Wright, 11 months, is under way in Prince George’s County Circuit Court. He is charged with two counts of first-degree murder, one count of child abuse resulting in death and a handgun charge. If convicted, he could be sentenced to life in prison without the possibility of parole.