TriMet announced a proposed ordinance that would codify the agency's authority to conduct random fare checks as a condition of riding the train or a bus.

The agency says it is clearing up confusion around fare enforcement after a circuit judge threw out a criminal case against a woman accused of evading fare on the basis that the TriMet officer who stopped her had done so unconstitutionally.

"The ordinance clarifies that TriMet does have the authority to require riders of our transit system to show they have paid their fare when requested by a TriMet inspector or police officer," spokeswoman Roberta Altstadt  said in a statement.

In March, TriMet official and a Portland police officer stopped Ana del Rocío, whose legal name is Rose Valderrama, and demanded to see her fare. She activated an electronic ticket on her phone in front of the fare inspector, who then asked for her identification. The interaction led to del Rocío being arrested.

A Multnomah County judge threw out the case against del Rocío after determining that TriMet officers or police who make stops to inspect fares need individualized suspicion. In other words, they should have a reason to believe that the person they stop did not pay to ride.

The Oregon Department of Justice declined to appeal the decision.

"The state's appeals are discretionary, and there are a number of factors we take into consideration when we decide to appeal a case, or not," says DOJ spokeswoman Kristina Edmunson. "We consider things like the likelihood of success on appeal and any other pending cases that are on related topics."

TriMet points to other judges' decisions that suggest the transit operator can check fares.

"Other judges have ruled differently," Altstadt said in her statement. "In another similar case, a judge noted, 'If you do not want to show your proof of fare, you do not get on MAX, because the requirement to be on MAX is to have valid fare and show proof upon demand, to an inspector or a police officer.'"

But the American Civil Liberties Union of Oregon, which represented del Rocío, says it will continue to take TriMet to court over what it believes to be unconstitutional fare inspections.

"For too long, TriMet has criminalized riders without fare and has subjected all riders, with or without fare, to suspicionless searches that violate the constitution," says ACLU legal director Mat dos Santos. "We hoped that TriMet would embraced the changes that are called for here. It is beyond disappointing that, since the judge's ruling, they have continued their flawed fare enforcement approach without addressing the underlying problems with this unfair system."