Research Papers / Research paper on death penalty - where to start? [12]

How to start and narrow a public policy research paper on Death Penalty

Hello,
I have to write a public policy research paper (7 pages) on the death penalty.
Per the instructor it is NOT to be a position/opinion/argument paper and should focus more on court cases or bills opposed to methods of executions.

My question is How to start and what can I focus on so that the paper is still cohesive. Do I perhaps pick a state and look at the history, process and statistics??

Thank You