Prosecutors have dropped one murder case against accused serial killer Homer Jackson but added another one in a new indictment filed Tuesday.

The indictment comes five months after the Oregon Supreme Court upheld the suppression of an alleged confession by Jackson. Jackson’s lawyers and prosecutors also are in multi-day pretrial hearings in Multnomah County Circuit Court, where defense attorneys are challenging Jackson’s fingerprint identification from at least one crime scene. A trial is set for Jan. 21.

The indictment drops all aggravated murder charges against Jackson in the death of Essie Jackson, 23, killed in March 1983.

Instead, it charges Jackson with the 1993 killing of Lawauna Janelle Triplet, 29, whose body was found in North Portland.

Four years after his arrest, Jackson, 59, faces charges in the asphyxiation deaths of four African American women who had been sexually assaulted and their bodies dumped in North Portland - three in the 1980s, and Triplet’s death in 1993.

On Tuesday, he pleaded not guilty to the new indictment, charging him with 15 counts of aggravated murder stemming from the four deaths.

A 9-year-old boy walking home from school located Triplet’s body on June 15, 1993, near a pedestrian overpass at North Going Street and Concord Avenue. She was last seen alive walking west on Northeast Alberta Street at about 1:30 a.m. on the day her body was found, police have said. Triplet was a known prostitute in the area, according to police.

Triplet died of abdominal injuries and strangulation, according to the state medical examiner’s office.

Dean Smith, one of Jackson’s defense lawyers, said he had just received the indictment. “We’ll take a good look at it,’’ he said.

The new indictment, issued more than three years after the initial indictment, continues to charge Jackson in the deaths of Tonja Harry, 19, killed in July 1983; Angela Anderson, 14, killed in September 1983; and Latanga Watts, 29, killed in March 1987.

Police arrested Jackson in October 2015 and has remained in custody since.

Police and prosecutors said similarities in the crimes helped investigators link the deaths. Each of the victims died of asphyxiation by strangulation or a ligature, was sexually assaulted and found with their shirts pushed up over their chests. They all walked the old Union Avenue, now Martin Luther King Jr. Boulevard, as prostitutes, authorities said.

Jackson’s original defense lawyer, Conor Huseby, reviewed the police evidence and Jackson’s hours-long, video-recorded interview with detectives and argued in 2016 that police had no evidence tying his client to Essie Jackson’s case and little linking him to the others. In cases where Jackson’s DNA was detected, police also found multiple other male DNA profiles in more incriminating locations at some of the scenes, defense lawyers have argued.

Multnomah County prosecutors until now have stood by all the charges, contending Jackson confessed to Anderson’s killing, “made inculpatory statements and admissions” when questioned about Essie Jackson’s death and that his DNA was found at three of the four crime scenes, according to court documents.

Though the new indictment no longer charges Homer Jackson with Essie Jackson’s murder, police and prosecutors said they still believe that Homer Jackson is responsible.

Prosecutors suffered a setback in the case when in December the state Supreme Court upheld the ruling in 2017 by Multnomah County Circuit Judge Michael A. Greenlick, who threw out statements Jackson made during more than seven hours of questioning over two days by two Portland cold case detectives when he was taken into custody. Greenlick found they were “made under the influence of fear produced by threats (and promises of leniency).’’

The state’s highest court found that the two veteran Portland police “detectives’ methods and inducements may have persuaded defendant to tell the detectives what they wanted to hear, whether or not that was the truth.’’

The state’s high court said it considered the totality of circumstances, including Jackson’s diagnosed schizophrenia, his significant problems with memory, that he wasn’t allowed to call his family until Portland police cold case Det. James Lawrence told Jackson that he felt "we are working together on this,’’ and that Jackson had provided incorrect details about some of the killings.

The new indictment charges Jackson with three counts of aggravated murder in connection with each of the deaths of Harry, Anderson and Watts, and six counts of aggravated murder in the death of Triplet.

It alleges Jackson killed Harry, Anderson and Watts in the course of committing and attempting to conceal the crimes of first-degree sexual abuse against each woman. The six aggravated murder counts against Jackson in Triplet’s death accuse of him killing her in the course of committing and attempting to conceal first-degree sexual abuse and first-degree unlawful sexual penetration.

-- Maxine Bernstein

Email at mbernstein@oregonian.com

Follow on Twitter @maxoregonian

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