Oregon set a new record in 2018 for the number of criminal defendants who are so mentally ill they cannot stand trial, a statistic demonstrating one element of the statewide mental health crisis.

Oregon State Hospital admissions data shows 718 defendants were made patients at the psychiatric facility last year under court orders to treat their mental illnesses until they gained the capacity to assist in their own defense. The figure was 609 in 2017.

That little-known judicial process, called “aid and assist,” ensnares many homeless people who are charged with crimes, often petty or non-violent offenses.

Every person charged with a crime, no matter how minor, has a constitutional right to understand what is happening in court. When a person is too mentally ill, a judge can order the defendant to a psychiatric hospital for treatment, halting the criminal case until the person is deemed “restored.”

No one undergoing aid and assist treatment – whether charged with a felony, misdemeanor or even municipal violation – has been found guilty of those charges, because the treatment takes place before a trial or plea deal.

Increasing numbers of defendants ordered to the Oregon State Hospital for aid and assist treatment are charged with low-level crimes, the state data shows.

Of the people hospitalized for trial competency treatment last year, 286 had been charged only with misdemeanors – a 30 percent increase from the prior year. Those charges tend to result in little or no jail time upon conviction.

The rise in cases has compounding causes. Homelessness and mental illness are pervasive in Oregon’s cities, and many living on the streets commit crimes such as trespassing or disorderly conduct by virtue of their homelessness. Others may commit crimes to feed illegal drug habits, which can cause mental illness and public outbursts to which police respond.

In Portland, a majority of arrests are of homeless people. Prosecutors across the state may zealously pursue convictions even for minor offenses and when a defendant is mentally ill. Judges hearing those cases are bound to make sure defendants are competent enough to make decisions. All of this adds to pressures at the door of the Oregon State Hospital.

Aid and assist treatment at the Oregon State Hospital costs taxpayers $1,324 per day, per patient. On average, a defendant racks up a hospital bill of more than $100,000 before returning to court to face their charges, according to state officials.

The treatment eats away huge chunks of Oregon’s mental health budget. Taxpayers spent about $489 million on aid and assist treatment over the last six years.

An investigation by The Oregonian/OregonLive published in January found the treatment is largely ineffective. Homeless mentally ill people are confined for long periods on low-level charges and are not provided with assistance once released from custody.

Others are kept in jail far beyond legal deadlines established to avoid violating defendants’ constitutional rights. Those actions have led at least five defense attorneys to ask a Washington County judge this month to hold the state hospital and Gov. Kate Brown’s Oregon Health Authority in contempt of court.

The judge, D. Charles Bailey, came close to making such a ruling earlier this month, but declined. Bailey is scheduled to hear two additional requests for a contempt ruling Tuesday.

-- Gordon R. Friedman

GFriedman@Oregonian.com

Staff writer Fedor Zarkhin contributed to this report.