In Pennsylvania, a panel has asked the state to place a moratorium on the death penalty so racial bias can be adequately researched.
I'm not sure this will go anywhere.
Unlike states that gleefully execute their prisoners (Florida, Texas), I think the Pennsylvania system is different. The appeals process is fair, although long. The governor personally reviews all cases, and our new current Governor has said he'd look into cases for new evidence, but he wouldn't throw out the death penalty, as he was a former Philadelphia prosecutor and mayor. (Incidentally, I am anti-death penalty. I don't believe in eye-for-an-eye.) Executions in Pennsylvania are very rare, unlike other states, and the state has only executed 3 people since the death penalty was reinstated in 1976.
Now in Pennsylvania, there are 245 people on death row, and 61 of them are black. The state panel sees bias in this (and nationwide, for whatever reason, there is a bias). 10% of Pennsylvania's total population is black, by the way.