For years, Drug Free Zones in Portland have proven to be a slippery debate. Under the decade-old rules, police officers can banish a suspected drug user or pusher for 90 days from large areas of Old Town and North Portland--even if there's no conviction; the officer needs only to believe that the person is engaged in some sort of drug activity.

But as long as these rules have existed, public defenders have also been trying to beat them back, saying they violate basic constitutional protections--namely, the right to a judge and jury.

In November 2003, Multnomah County Circuit Court Judge Michael Marcus agreed that the rules ran afoul of basic constitutional protections. At the time, he wrote a refreshingly humane opinion that "mere suspicion" of drug activity was not proof enough to punish someone. He went on to say the laws were especially onerous to the "poor, homeless [and] mentally ill" and likened them to Elizabethan Poor Laws which tried to exile beggars from London.

But 48 hours later, then-Mayor Vera Katz convened city council and tweaked the DFZ rules to read that a police officer would need a "preponderance of evidence"--as opposed to "mere suspicion"--before kicking a person out of the DFZ. It was a hairline change--and one left largely to the discretion of the police officer. Even so, that alteration was enough for the DFZ to squeeze past constitutional concerns and be reinstated.

Since then, cops have been back to business as usual, booting dozens of people at a time from the city's DFZ--but defense attorneys have not given up, and have been looking for new angles to attack the re-worded DFZ. On Friday, that debate once again landed in Judge Marcus' courtroom.

As before, the legal debate struggled over whether DFZ were constitutionally fair. But this time around, the public defender presented a particularly pointed attack: That the DFZ unfairly and disproportionately affects African American men in town. The thrust of the public defender's argument was that African American men account for the vast majority of DFZ exclusions.

For the first three hours of debate, attorneys squabbled over whether the success of the DFZ should validate dubious constitutional practices. At times, that argument veered from a theoretical discussion into the gritty reality of street law. The city attorney tried to argue that without DFZ allowances officers are impotent to fight open-air drug markets.

"We're not in that position where the city can depend on the criminal justice system to pick up the slack," explained the city attorney. Pleading that the police need more tools to fight the city's drug trade, the attorney went on to explain that officers need a quick and ready way to chase away suspected users and pushers.

Judge Marcus conceded that such approaches to crime fighting have shown results, and that he has "immense respect" for "evidence-based problem solving." But, he added, "I question the constitutionality."

After all, the same justification could be used for, say, roughing up a suspect when he's not forthcoming with a confession. The result may be desired, but in criminal law--especially when considering the constitutional fairness of police methods--the ends do not necessarily justify the means.

Ultimately, Judge Marcus cut off the discussion about approaches to fighting the drug trade: "We're having a discussion that's for city council," he explained, clearly trying to veer away from anything that could be labeled as judicial activism.

The remainder of the courtroom debate focused on what the public defender called an unfair impact of the DFZ on African American men. With a young black man sitting next to him, dressed in a prison jumpsuit, the public defender Chris O'Connor tried to show that the number of exclusions issued to African American men was nearly double that of the population of black men in those neighborhoods. If true, Judge Marcus could decide again that the DFZ violate constitutional protections--and that police are unfairly profiling African Americans as suspected drug dealers and users. In an explanation that made the city attorney squirm, public defender O'Connor intoned that the disproportionate prosecution of African American men was both race- and class-based discrimination. He pointed out that policing street-level drug dealing in Old Town focused on black men while white Pearl District residents freely snort cocaine in their lofts.

A decision from Judge Marcus is expected before April 19, when several other DFZ challenges are scheduled for trial.