The man accused of gunning down eight people at a Seal Beach hair salon in 2011 will plead guilty to eight counts of special circumstances murder and one count of attempted murder, his lawyer said Monday.

Scott Dekraai, who, according to prosecutors, was seeking revenge on his ex-wife when he opened fire at the Salon Meritage, has "felt for a while that he really needs to give at least the victims the sense that he's not seeking to have this go on forever," said his lawyer, Assistant Public Defender Scott Sanders.

"He thinks he owes to them at least the knowledge that he's willing to accept responsibility."

There is substantial evidence in the Oct. 12, 2011, shooting: Dekraai was arrested after he was driving away from the scene and soon confessed to investigators, according to court records. Dekraai had been involved in a custody dispute with his ex-wife, Michelle Fournier, who worked at the salon and was one of those killed, prosecutors said.

He still faces what will probably be a long trial to determine whether he receives the death penalty or life in prison without the possibility of parole. California defendants cannot use a plea agreement to accept death.

Dekraai had previously offered to plead guilty in exchange for a sentence of life in prison without parole, but that offer was rejected by the Orange County district attorney's office because prosecutors refused to drop the death penalty. The guilt portion of his trial is set to begin June 9.

The intended plea does not involve a negotiated agreement for leniency, and prosecutors said little had changed as a result of it.

"The battle in this case has always been the penalty phase," said Senior Deputy Dist. Atty. Scott Simmons.

Dekraai's trial, which like many death penalty cases has been slow to start, has been delayed even longer as the court examines defense allegations of the improper use of jailhouse informants in this case and others.

Since mid-March, the court has heard testimony from prosecutors, law enforcement and informants as it examines whether jailhouse informants were, as the defense says, repeatedly deployed in violation of the constitutional rights of Dekraai and other defendants, and information routinely kept from defense attorneys.

During the hearing, the head of the district attorney's homicide unit acknowledged that evidence has not been disclosed in certain cases, a revelation that could lead to new trials for some convicted criminals. Last week, prosecutors said they would no longer seek to introduce recordings of Dekraai speaking to informant Fernando Perez, which they hoped would help prove that Dekraai deserves the death penalty.

Orange County Superior Court Judge Thomas Goethals said Monday that Dekraai's plea does not resolve the motions filed as a result those allegations, and he indicated that he will continue hearing testimony on the informant issues.

Paul Caouette, whose father David was shot and killed in the parking lot outside the salon, said he had mixed feelings about Dekraai's decision to plead guilty.

"I don't know if it's any resolution," he said. "I think accepting his guilt, that's a good thing; but in my opinion, he deserves the death penalty."

Like many of the victims' families, Caouette has spent much of the last 2 1/2 years attending hearings as the case winds its way through the court system. He said he would continue to do so through the death penalty trial.

"I'll be here as much as I can," Caouette said.

Bethany Webb, whose sister was killed and mother was wounded in the shooting, said she does not believe in the death penalty. But she said Dekraai has not earned any sympathy for agreeing to the plea.

"He's not doing this because he's a good guy," she said. "This is just something his attorney is doing so he can go into that courtroom and say, 'Ladies and gentlemen of the jury, [Dekraai] did this because he felt bad for the families.' But he's not doing it because of that.

"He saunters in that courtroom and smiles at us," she added.

Dekraai is expected to enter a formal plea Friday.

paloma.esquivel@latimes.com