Who is a decisionmaker in your community who can make change? A mayor? A police superintendent? What changes can they make to remedy the problem? Are there specific policies that could restore faith in your local police department? Body cameras? An independent review board for misconduct? Is there a particular case that should be investigated?
Lastly, your research (your interviews) need to clearly support your recommendations. What did you learn from your interviews? What changes can you recommend based on your findings?
