PORTLAND — A federal judge in Oregon has found that an immigrant woman’s constitutional rights were violated when she was held in jail without probable cause at the request of immigration authorities, one of several recent federal court decisions to scrutinize the practice of keeping people in jail after they’re eligible for release so that they can be considered for deportation.

The rulings make it clear that local officials are not required to honor immigration authorities’ requests that someone in custody continue to be held even though their original charges were resolved or they are eligible for bail, and that local jurisdictions may be held liable for doing so.

The rulings have spurred several jurisdictions to announce they will no longer honor requests for such holds. Previously, some counties and states had already limited use of the practice, arguing it is expensive, erodes immigrants’ trust in law enforcement, and drags people with minor infractions such as traffic violations into deportation.

The decisions come as immigration reform has stalled and the Obama administration is being criticized for deporting mostly people who have not committed a serious crime — despite its stance to focus on dangerous criminals.

Requests that an immigrant be held are sent to local law enforcement by the U.S. Immigration and Customs Enforcement, or ICE. The agency knows who is being booked into local jails because of an information-sharing partnership between ICE, the FBI and local jurisdictions.

The notices request that the person be jailed for an extra two days, excluding weekends and holidays, so that ICE can initiate an investigation and take the person into custody.

But immigrant-rights advocates say ICE has made mistakes in the past, incarcerating U.S. citizens, people who have not committed any crimes, or those arrested on misdemeanors.

“They do it in a dragnet manner without first doing the investigation upfront, sometimes before a local district attorney has even signed off on the charges. So it results in the unjust incarceration of a lot of people who are not deportable at all, or who are not found guilty in the criminal process,” said Kate Desormeau, an attorney with the American Civil Liberties Union.

In recent years, California, Connecticut and more than a dozen jurisdictions around the country have stopped or limited their compliance with the so-called immigration detainer requests. Lawmakers in Massachusetts and Maryland are considering similar legislation. On Wednesday, the mayor of Philadelphia signed an executive order limiting the use of such holds.

ICE has said that the requests are optional. The detainers generally are not accompanied with a warrant.

But many local law-enforcement agencies say they have treated them as orders because the requests cite federal regulation, which states that a law-enforcement agency “shall maintain custody of an alien” once a detainer request has been issued.

“The fact that the detainers contain both language of request and command has led to conflicting interpretations as to whether the immigration detainers provide legal authority for the continued custody of the people named in the detainers,” Clackamas County Sheriff Craig Roberts wrote in a letter announcing the suspension in the use of detainers.