SEATTLE -- Did you know it's against the law in Seattle and King County to ride a bicycle without a helmet. About a third of cyclists don't know or don't care.
The Traffic Safety Commission says 30 percent of cyclists in Seattle and King County don't wear a helmet and most are young adults.
Seattle Police wrote 447 tickets for failing to wear a helmet last year, but enforcement is weak.
Police say they prefer to educate cyclists to go buy a helmet rather than slap them with a $103 fine.
Dr. Fred Rivara of UW Medicine says, "They enforce the laws against not using your seatbelt. They enforce the laws against not using a motorcycle helmet, and therefore, I think they should enforce the laws against not using your bicycle helmet.
If strictly enforced, Dr. Rivara believes many brains could be saved. Instead, cyclists says they know they'll get off easy.
"Most of the time they say, 'Don't you know you're supposed to have a helmet? Oh yeah, I don't have one right now.'"