PORTLAND, Ore. (AP) — A man waiting to testify in an Oregon murder case has been held in jail as a material witness for nearly 900 days, though he has committed no crime.

Legal experts tell The Oregonian that it’s exceptionally rare to be held as long as Benito Vasquez-Hernandez.

The 59-year-old man has been incarcerated at the Washington County Jail for 897 days, or just shy of two and half years. His bail was set at $500,000.

Prosecutors say Vasquez-Hernandez’s testimony is essential to their case, and he probably wouldn’t show up to court if released. His elder son, Eloy Vasquez-Santiago, is suspected of killing Maria Bolanos-Rivera of Hillsboro in 2012.

Civil rights advocates say Vasquez-Hernandez should be released because he is poor, has no formal education and appears to have very low mental competency. He’s also an immigrant who doesn’t speak English and doesn’t understand the American justice system.

Moises Vasquez-Santiago, circa 2012 (Washington County Sheriff's Office)

Vasquez-Hernandez’s other son is the second material witness in the case. Moises Vasquez-Santiago was released last fall after being diagnosed with schizophrenia while serving 727 days in jail.

Both material witnesses were arrested two years ago in California, after Vasquez-Hernandez told detectives he had seen blood in the minivan his elder son drove, and the younger son said his older brother had admitted to him that he had stabbed the woman to death.

Two days later, the older brother, Eloy Vasquez-Santiago, turned himself in to authorities. He told investigators that he had worked with Maria Bolanos-Rivera at Oregon Berry Packing Company in Hillsboro, and they had gone out on a date the day she disappeared. Eloy Vasquez-Santiago told police he stabbed her because she had insulted him, but did not tell them where the body could be found.

In Oregon, a judge can keep material witnesses in custody indefinitely until they testify, or release them pending trial. But typically, detention lasts less than a week.

Vasquez-Hernandez’s defense attorney tried to get him to give a sworn statement in a video deposition. But Vasquez-Hernandez was so flustered, he kept repeating he should not be in jail and he’s innocent — until the judge threw him out.

Senior Deputy District Attorney Jeff Lesowski said he sincerely regrets keeping the witness locked up for so long, but he sees no alternative.

“Normally the speedy trial provision would kind of act as a limit on how long a witness could be held,” said Lewis & Clark Professor Tung Yin. “The material witness statute is designed to allow either side — the government or the defense — to say, ‘Hey judge, we need this person to show up for trial. Here’s why we think they’re not going to show up for trial, so can you just hold them until trial?'”

Jann Carson with the Oregon ACLU said they have long questioned the use of jails for detention of material witnesses who have not committed a crime.

“We want to make sure the government has a high burden to meet before they can hold someone,” Carson said. “We put electronic monitoring bracelets on individuals to track their whereabouts, so there seems to be other options available. I hope that those were explored.”

Eloy Vasquez-Santiago’s murder trial is scheduled to start Tuesday.

The attorney for Vasquez-Hernandez told KOIN 6 News he hopes his client can testify and be released sometime next week.KOIN 6 News contributed to this report.