Right at the outset, the officer told them it couldn't be attached
Since I am working on the transcript today for youtube, here is the begining.
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>>Off1: What’s going? What’s the sign say?
>>B: The sign actually says “Taxes” and then “equal sign” and then “theft”
>>Off1: Okay. Well you can’t hang it from the overpass that’s the only issue
>>B: Oh there’s a law that says I can’t hold a sign?
>>Off1: Well I’m saying that they don’t want it on there. You’ll have to ask the CHP.
>>B: I’m just wondering if there’s a law.
>>Off1: I don’t know if there’s a law.
>>B: Cause if there is –
>>Off1: As long as you guys aren’t hurting anything.
>>B: Ya, I mean
>>R: We’re just standing here.
>>Off1: As long as you guys aren’t defacing property I don’t have a problem with it. I’m just saying, CHP might come by and tell you to move along cause you are on state property.
>>B: Well if they come here and they tell us that we can’t have it-
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From there it becomes about the officer demanding things he doesn't have a legal right to have and us asserting our rights.
The Officer didn't know about PC 602 (f) until after we had been arrested.