Bob,
Since no one else took a shot at it...I'll give it a try!
That law prohibits giving special rights or immunities to any one based on race, treaty rights, etc....
It would certainly prohibit a caucasian only fishing season...or a lake that is only open for mexicans...or a limit of two steelhead for germans, but only one for the rest of us.
I'm guessing that's not what you're looking for, though...I'm pretty sure you want to know about the "treaty rights" part...and the answer is a lot easier than for the above statutory questions.
The answer?
It has absolutely no legal application whatsoever. No one, and I mean not even one, Indian has ever been arrested, nor has any tribe been sued, under this statute.
The reason that they haven't is that they can't be. The law itself violates the United States Constitution, which states that the laws of the U.S. cannot be usurped by any state laws.
This includes federal court rulings.
As we all know, the federal courts have repeatedly, and without fail, found that signatories to the Treaties of Point Elliot, Point No Point, Medicine Creek, etc., all have off-reservation treaty fishing rights, rights that are paramount to our abilities to go fishing.
Why is the law still on the books? Probably for a couple of reasons. One, it still prohibits other types of discriminatory practices...even though that wasn't the point of writing it. Two, it might be that someone just hasn't done it yet, lazy or not important enough to do it. Or three, the state wants you to think that they tried to do something about it, i.e., tried to prohibit treaty fishing, even though they knew they couldn't.
I can tell you this, though, that law is the butt of many jokes in the AG's office.
Fish on...
Todd.
P.S. Even though it has been stated on this BB and all the others, repeatedly, that the State can do nothing to limit the treaty fishermen's right to fish...folks repeatedly bash WDFW for not doing something to limit treaty fishing. Here's the answer to your prayers...this law. Problem is, it doesn't matter.
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Team Flying Super Ditch Pickle