that law has a gray area with "prevailing and lawful"....the lawful speed limit on the freeway is 45-65 if the prevailing speed is 15mph such as sitting in rush hour, that speed is unlawful but it is allowed because its the prevailing speed and the fastest you can go if youre doing the speed limit in the fast lane, somebody passing you would not be able to do so safely. they dont get a free pass to go however fast they want. if youre doing the speed limit you are not required to move over for them. if you are moving slower than the prevailing and lawful speed, you are required to scoot over and let the faster traffic pass. so if youre doing 65 in the fast lane, you cant be pulled over for it because you are doing the speed limit and the law says that you are only required to move over if youre under that limit there could be some wiggle between prevailing and lawful in regards to somebody lawfully driving 45mph in the fast lane while prevailing traffic is moving 65. but just because you want to drive 90mph, doesnt mean people doing 65 are required to move over and let you past