Life in prison is just a delayed death sentence.
I dont think the two are equivalent
Both can be ended via suicide, if the inmate so chooses.
If there somehow end up being Pennsylvania or federal charges against him in connection with the murder, those criminal law systems still have the death penalty.
He does currently face some Pennsylvania charges as well, such as firearms charges in connection with the encounter where he was arrested, but none of those are severe enough to warrant a death sentence.
The difference between those two and a non-imprisoned life is... significant.