Multnomah County prosecutors are parrying the latest attempt to dismantle Portland's camping ban, insisting the law doesn't infringe on the right's of the city's homeless, or criminalize people for their homelessness.

In a legal memo filed yesterday [pdf], the district attorney's office says claims the ban constitutes "cruel and unusual punishment" and violates the Oregon and US constitutions should be tossed when a Multnomah County judge considers them later this month.

"There are not any constitutionally protected interests that Portland's camping ordinance invades," says the six-page filing.

The arguments are in response to a challenge being mounted against the ban by the state's largest public defense firm. As we reported last month, attorneys with Metropolitan Public Defense Services have been working out ways to attack the ordinance, which they say is being used with troubling frequency to leverage criminal charges against Portland's homeless.

Public defenders found a potential battleground for that fight in the case of Alexandra Barrett, a young homeless woman who's been arrested again and again in the last year on camping-related charges. Whereas many defendants are happy to take a deal and be rid of charges, Barrett's been intent on fighting them.

That gave attorneys room to make some familiar arguments against the city's camping ban, which makes it a misdemeanor to camp on public property. Since the city lacks enough shelter space to accommodate every homeless person, defense attorneys say the camping ban essentially criminalizes people for doing what they must to survive. They've also argued that the ban tramples the constitutional right to travel, since a homeless person traveling through Portland could be ticketed or arrested when they set up a camp site.

Last month, the prosecutor's office asked a judge for 8 weeks to respond to the motion, a sign the office was taking the matter seriously. But the memorandum filed yesterday is actually relatively scant.

It denies that the camping ban criminalizes homelessness, and points out an Oregon appeals court has made a similar ruling in the past. And is says the city's small enough that no homeless person would be forced to bed down for the night when passing through.

"It is easy to travel through the city limits or Portland without having to stop, set up camp, and violating the camping statute," the memo says. "Portland is not so big that one would be forced to stop and set up camp in order to pass through."

At least one Multnomah County judge has ruled the city's camping ban unconstitutional in the past, but the city largely ignored the 2000 ruling, noting other county judges have found it legal. The Barrett decision, if it comes down against the city, could carry more weight. It's being decided by Multnomah County Circuit Judge Stephen Bushong, the well-respected jurist who forced the city to ditch its controversial sit-lie law when he found it unconstitutional in 2009.

Arguments on the motion to dismiss Barrett's case are set for January 23.