Per San Francisco Transportation Code 7.2.12 it is illegal and unsafe to ride on the sidewalk if you are over the age of 13. Not to mention there have been a number of recent news articles that also seem to suggest there's a high level of meth use among people who bike on the sidewalk. That's why we're creating a city-wide sidewalk biking offender list. We won't be listing names or showing faces (we're not evil, come on), we will be taking your eyewitness accounts of people riding their bikes on the sidewalk and adding them to our offenders map below.
I didn't know biking on the sidewalk was a sign of meth use.