I think that Judge Fisher beats Judge Ikuta in this one.
People are entitled to demonstrate under the First Amendment. The City of Seattle lets them, of course, but can (obviously) subject demonstrations to reasonable time, place and manner restrictions. So, for example, sometimes you can close off the streets and let demonstrators walk a particular path, and other times -- for example, with very tiny protests -- you can make them use the sidewalks. That seems fine.
But the City of Seattle vests unlimited discretion in the Chief of Police to decide when a particular protest is relegated to the sidewalk and when they can use the streets. And that discretion has been utilized -- as one might expect with unlimited government discretion -- in a potentially abusive manner: namely, the Chief of Police has been much more likely to put greater restrictions on political marches (e.g., to limit them to the sidewalk ) than other types of marches (e.g., sports gatherings). So, for example, the Chief of Police has been more likely to say to political marchers "You've got to have at least 200 people show up to be able to march on the street" than to non-political marchers. And when the annual march against police brutality transpired in Seattle, guess what? Yep. Relegated to the sidewalk.
Judge Fisher says that statutory structure doesn't comply with the First Amendment. I agree. Judge Ikuta dissents, but I think undervalues the danger of unlimited governmental discretion in this critical area. I'd have little problem with a statute that says, for example, "Any march under 200 people must normally stay on the sidewalk, whereas any march with over 200 people may normally march on the street," and that provides for particularized exceptions for particular reasons. But I have a big problem with a statute that essentially says "Any march the Chief of Police likes can march on the streets, but any march the Chief of Police doesn't like has to stay on the sidewalk."
So, like Judge Gould, I'd have to vote with Judge Fisher on this one.