So those 10 Occupy Portland arrests this morning at the federally owned Terry D. Schrunk Plaza? It's possible they didn't have to happen when they happened.

Mayor Sam Adams' office told me this afternoon that the Portland Police Bureau has no formal cooperation agreement in place with the Federal Protective Service or Department of Homeland Security and that, when the feds finally asked for help to clear the campers, it "looks like we technically could have declined."

Of course, the bureau, acting on the orders of the mayor—who has forbidden any expansion of Occupy Portland past Chapman and Lownsdale squares—pretty easily agreed. Dozens of officers swarmed the site around 4 this morning and briskly, if peaceably, arrested any of the sleepy campers who wanted to be arrested, while holding back the rest.

Adams' spokeswoman, Amy Ruiz, says city officials had been in talks with the feds all day yesterday, ever since the first tents went up in Schrunk early Monday morning.

"Practically speaking, they needed assistance, and the action was aligned with what the mayor has said about expansions," she reminded me. "That, and the park is in our city, surrounded by our streets—it just makes sense to assist to ensure a successful and peaceful action when it's in our broader jurisdiction."

I asked what would have happened if the mayor's office had said no—was the worry that federal officers would have been less polite if they'd taken the lead? (It also occurred to me, after our chat, that maybe the feds wouldn't have had the numbers to safely make arrests on their own). But Ruiz called that a "what-if," and said the city never entertained the notion, let alone pondered what might have happened.

Says Ruiz: "We didn't consider saying no," eventually reminding me again that "It's very consistent with what we've said" about expanding the campsites to other parks. I noted that the reason the mayor gave for cracking down on Jamison this weekend—that it's residential—barely applies to Schrunk, adjacent to city hall, the Justice Center and Chapman Square.

That still didn't matter, I was told. The feds asked. Portland agreed. And expansion, to other parks at least, is not on the table.