U.S. Death Penalty--what about state law speeds the process?

This is a GQ, but we’ll see. When any discussion about the death penalty in the U.S. comes up, it’s usually the federal courts that are blamed/hailed for slowing down the process, but it would seem to me that the individual states have a lot to do with it.

Texas is notorious for lining them up. Florida and Virginia are in the second tier. Other states like Pennsylvania and California have a large death row population but very few executions.

Since all states have the same federal government, what is unique to each state laws that allow some relatively quick (10 years) executions to long stays on death row (20+ years)

I know that nobody wants to cite individual state codes, but is there a common element in the “quick” states vs. the “slow” states?

I’ve heard that Texas executes more, but that’s always been in the context of Texas having the death penalty apply more. Do you have any stats that say Texas moves them through the system faster?