Monday morning, the defense asked the judge to consider a sentence of life without parole. That motion was denied.
The judge listened to several victim impact statements before handing down her sentence of the death penalty. Green will meet his fate at San Quentin.
As he did throughout the trial, Green showed no emotion during his sentencing. But he did show an occasional smile during breaks.
Bonaminio's mother, Gerri, was present for the sentencing. She said she hopes to be there the day Green is put to death because that will be a day that she smiles.
"The defendant cowardly and brutally took my son's life without cause and with hate. I will never forget, and I will never, ever forgive," she said between tears.
Green was convicted last month of murdering Bonaminio. Earlier this month, the jury recommended the death penalty for Green.
Bonaminio, an Iraq war veteran, tried to stop Green for a traffic violation in 2010. Green beat the officer with a steel pipe and then shot Bonaminio with the officer's own gun.
Bonaminio's family said the trial has reopened many wounds, but they are hoping Green's sentencing will help them move on.