[kelnos]

That's seems unnecessarily confusing. Why even bother with the red arrow at all then? I guess it could be useful in cases where the straight-through traffic is green, but you want right-turning traffic to stop before turning, but is that common? Or even a useful thing? Like, I feel like if you've set things up that way, maybe the intersection is just designed poorly.

[mypalmike]

It is definitely confusing. In Washington state, right red arrow does not prohibit turning on red. I learned this after people started beeping at me to go at such an intersection. And yes, that intersection (Queen Anne and Mercer in Seattle) is confusing and poorly designed.

[toast0]

I don't think I've seen many intersections with red arrows unless there is a dedicated turn lane, where green yellow and red are all arrows. If it's a right turn in a right on red jurisdiction, without a sign expressing no right on red, why would red arrow be different than red circle?

[sokoloff]

MA allows right on red arrow after stop (absent a sign to the contrary). There are intersections where right on red is prohibited to protect a pedestrian walk phase that’s aligned with the green for straight ahead traffic.