Just so it is clear, I am playing the devils advocate here. I personally would not carry a rifle if I were along for someone else's hunt and did not have a license for something to hunt. I may carry a pistol but that would depend.
The point I am making is that there is no regulation prohibiting it so the LEO has no grounds for issuing a ticket unless there is further evidence supporting a violation. There are regulations (in some places, not sure in WA and don't feel like looking right now) against possessing a spotlight on your person or in the vehicle during a big game season so thereby that would be a violation even if it were a broken light.
I am just saying that in this case the burden of proof is sadly lacking and if the LEO were to make an issue of it and they were not a reasonable (reasoning) person issued a ticket then it should be an easy dismissal. At that point I am not sure what recourse is available for the wronged party (non-hunting gun bearer) but imagine there is something. Though the legal umbrella LEOs carry is pretty big so there is probably little retribution that could be obtained.
It is kind of like saying that you head out in the boat fishing with a non-fishing friend and they get cited for fishing without a license because there is an extra rod in the boat.
Agreed in principle, but in the field on the side of the road, not likely to get reasoned out that way given WDFW's "write'em like they see'em" point of view.
More likely the "tell it to the Judge" and rifle or rifles taken, here are your citation(s) and court date(s)secenario, then your out of state uncle either has to stay here for months to resolve it, travel back & forth to resolve or just give up and take the loss, which depending on his resident state, may loose hunting prividledges there as well. And that isn't counting the dollars towards an atty.
Read through some of RTSpring's threads about his encounter and the time and costs and losses, then see if it really is worth the risk.
Is it really worth all that potential trouble for your uncle, not to mention, since he is with you, you potentially could be charged with Aiding and Abbetting.