https://www.factcheck.org/2015/11/trump-retweets-bogus-crime...
Starting with the most obvious point, the Crime Statistics Bureau of San Francisco doesn't exist.
Availability: A heuristic for judging frequency and probability
edit:
> The reality of the availability bias isn't in question, it's whether or not people's belief about police brutality is accurate
It would be nice to have some objective evidence showing why this example is a special case immune to availability bias.