Originally Posted by NWRVR
Our Oregon traffic law requires the right lane traffic to slow down to allow on-ramp vehicles to merge if both will be at the same spot in the right lane at the same time. If there is an accident, the right lane vehicle is at fault.
I read the Oregon guidance as saying the highway traffic has the right-of-way, which is the common condition in the US:
You must yield to traffic already on the freeway. Use your mirrors and
check your blind spots before merging. Adjust your speed to match traffic already on the freeway. Keep moving if at all possible. Drivers behind you expect you to speed up rather than slow down.
I found that on the Oregon DMV site in the driver's manual
. The text of the applicable law is listed here
, down on page 24 (it's searchable, 811.285). Perhaps you're thinking of the new rule (relatively new in many states, including here in Texas) requiring freeway traffic to merge left where possible when passing police and other emergency vehicles stopped on the right with their emergency lights on?
That said, wherever it's safe to do so I'll generally move left to allow merging traffic into the right lane, as much for the fact that so many mergers don't get up to highway speed early enough as for reasons of politeness.