In June 2020, I saw a poll that terrified me: A majority of white Americans genuinely believed that Black suspects are not any more likely to be mistreated by police than white suspects. It wasn’t just that a majority of white Americans thought that most police officers were good people or that there wasn’t overt racism among officers—a majority of white Americans denied that implicit or systemic biases lead to race-based discrepancies. At all.

I’m an analytical person and a social scientist. I very much seek evidence and adjust my beliefs in light of it. While I have read a lot of research on racial disparities in labor markets, education, loan programs, and other aspects of life, I had not actually read more than a couple of papers on policing. I started to read, hoping to educate others along the way, and imagined that I would review a dozen or so papers.

It’s proved to be a much larger effort than that. Researchers from disciplines as varied as criminology, health, economics, computer science, communication, psychology, and many more, have all documented (using a variety of analytical methods) widespread racial disparities in law enforcement.