OAKLAND -- A judge will begin hearing evidence Wednesday on whether the city can restrict the activities of 40 people it says are members of the Nortenos street gang.

Judge Robert Freeman will decide whether to issue a preliminary injunction that would temporarily order some or all of the defendants to obey curfews and refrain from gathering together or wearing certain clothes inside a proposed "safety zone." City Attorney John Russo announced the injunction lawsuit in October, calling it a potentially valuable tool against a gang authorities say is responsible for half the violent crime in the Fruitvale district.

At a hearing Monday, Freedman ordered the defense to call no more than five witnesses, though he may allow more after those witnesses are heard. The evidence hearing is unlikely to be finished in one day and the process could go all the way to a full trial on permanent injunctions in November.

"The judge is not sympathetic to our requests for more time," said Michael Siegel, one of the five volunteer attorneys representing 30 defendants, 10 of whom are already in law enforcement custody. "This puts a lot of pressure on us."

The defense will largely focus on a two-year statute of limitations on public nuisance suits, Siegel said, arguing that the criminal history of each client will not be usable in the case unless the crime was in the last two years.

Siegel also touted a vote by the Oakland teacher's union opposing the injunction.

Betty Olson-Jones, president of the Oakland Education Association, said injunction opponents -- including Siegel, whose father, Dan, served on the Oakland school board -- approached union leaders to present their argument. She said the vote, taken at a recent meeting of union representatives, was unanimous.

While no one named in the injunction is under 18, Olson-Jones said teachers worry the policy will affect Oakland students, particularly black and Latino teenagers. She said she is concerned that people with no gang ties will be stopped and questioned, regardless of how narrowly the injunction is focused.

Another new player in the case is attorney Dennis Roberts, who said he is representing Eastside Arts Alliance and other "interveners" -- groups he said are not party to the lawsuit but who would be harmed by it because they perform gang outreach efforts, often at night, and would be unable to reach their clients effectively if those clients aren't allowed to leave the house or sit in the same room with each other.

Russo spokesman Alex Katz said the injunction has exceptions written into it to allow gang members to seek counseling and aid.

"The point of this is to get them out of the gang life," Katz said. "If they're taking steps to do that, then they should be able to."

Meanwhile, attorneys on both sides offered up some documents relating to the case this week:

Siegel & Yee -- which employs two lawyers fighting the injunctions as well as Councilmember Jane Brunner and Dan Siegel, a legal adviser to the mayor -- had been ordered by the judge to show how it's been keeping its work on the injunction separate from those people working for the city, thus avoiding a conflict of interest.

According to the filing, the attorneys fighting the injunction are working on a different floor in the building Siegel & Yee occupies, and the office has "a strict prohibition" of conversations with Brunner on the topic of the city's legal affairs.

Russo's office and police have submitted a report to the Public Safety Committee for its Feb. 22 meeting, after Councilmember Pat Kernighan (Chinatown-Lake Merritt) asked to know about the injunctions' costs and impacts.

The report states that an earlier set of injunctions against 15 people in North Oakland were followed by a drop in drug activity of almost 70 percent in six months, though other crimes went up slightly.

The police work on both injunction cases has cost roughly $200,000 in staff time, while legal work has totaled almost $450,000 between the two cases, the report states.

Staff writer Katy Murphy contributed to this report. Contact Sean Maher at 510-208-6430.