The death penalty may not have been in effect when Manson was on trial, but it likely was still in effect at the time he committed his crimes.
Not that it matters since virtually no one on death row is ever actually executed in California.
Hmmm.
Manson is over 60 years old. The trial will last 2-5 years. The appeals will go another 5-10 years. Even if convicted, he will not be put to death until he is over 80 years old.
Chances are he will die of old age.
I could be wrong, but as I recall, there was a death penalty in effect when the murders took place and he was sentenced to the death penalty at his trial. That death penalty law, however, was thrown out some years later and Manson got a straight life sentence. The current CA D/P law was passed well after all this, and cannot be applied to him for these old crimes.