John T. Earnest of Rancho Penasquitos pleaded guilty to a 113-count hate crimes indictment, the statement said. Prosecutors said the plea agreement includes a recommended sentence of life in prison plus 30 years.
In addition to the synagogue attack on April 27, 2019, Earnest admitted he tried to set fire to the Dar-ul-Arqam mosque in Escondido, California, on March 24, 2019, the Justice Department said.
Prosecutors said they found a manifesto allegedly written by Earnest, in which he penned anti-Semitic and anti-Muslim statements, including “I can only kill so many Jews” and “I only wish I killed more.”
Armed with a Smith & Wesson M&P 15 assault rifle, Earnest, who was 19 at the time, killed 60-year-old Lori Gilbert Kaye, who was at the synagogue to honor her late mother, and injured three others, including the rabbi and an 8-year-old girl.
They were among more than four dozen people inside the synagogue at the time.
In July, Earnest reached a plea agreement on the state charges, accepting life in prison without parole on the murder and attempted murder charges. The agreement spared him from the death penalty.