Sunday afternoon a woman in her 60s suffered a life-threatening head injury when a 21-year-old male cyclist struck her as she walked in a pedestrian lane (commonly referred to as "the sidewalk") near Market and Stockton Streets.

The victim was taken to S.F. General Hospital around 12:30 p.m. yesterday. Although early reports said the cyclist received a citation and was released at the scene, SFPD spokesman Officer Gordon Shyy said the investigation is ongoing.

While there may be some legal gray areas for bicycle-based aggression such as (allegedly) trying to beat yellow lights, the San Francisco Transportation Code Sec. 7.2.12 is pretty clear that it is illegal to ride your bike on the sidewalk if you're over the age of 13. It's also really fucking annoying and you're a grownup on a bicycle, so take a bicycle safety course and get back on the streets already.

Also, anecdotal evidence shows many people riding bicycles on the sidewalk in San Francisco are also meth users. So there's that.