PROVO -- Officials now believe a Pleasant Grove physician may have killed his wife, and have also uncovered evidence that he claimed to have killed other people.

New documents filed in 4th District Court detail a search warrant for emails belonging to Martin MacNeill, 55, who is currently in federal prison, and his then-mistress, Gypsy Willis. They state that MacNeill had "opportunity, the motive, the psychological disposition and the capability" to kill his wife, who was found dead in a bathtub in 2007, shortly after having plastic surgery.

The documents were filed in March and granted investigator Jeff Robinson permission to search eight Yahoo email addresses belonging to MacNeill and Willis. The documents reveal that MacNeill may have killed his wife with a lethal cocktail of drugs because he no longer loved her and wanted to conceal an affair with Willis.

The documents and search warrant reveal a complex and sordid narrative leading up to Michele MacNeill's death. In April 2004, the documents state, MacNeill began an affair with Willis, who allegedly later told her roommate she wanted to "get rid" of Michele with either drugs or by cutting the brake lines on her car.

Later, in 2005, MacNeill allegedly told another mistress, Anna Osborne, that he wanted to kill his daughter Vanessa because her drug problems were an "embarrassment" to the family. He also told Osborne that he had killed his brother and made it look like suicide, and bragged about killing his handicapped patients at the state Developmental Center in American Fork, where he was clinical director, according to the documents. Osborne reportedly told her psychiatrist that she was having an affair with a serial killer.

In 2006, the documents state, Michele told a friend that Martin wanted a divorce because he claimed to not love her or their children. Then in March 2007, he reportedly asked Michele to have plastic surgery. Michele consented, despite her initial objections.

Around the same time, Michele reportedly expressed suspicions to her daughter Alexis Somers that Martin was having an affair. Somers and Michele eventually discovered Martin was communicating with Willis using his cell phone, the documents state, but he denied the existence of any relationship, saying Willis was a tenant in their rental property.

According to the documents, Michele was prescribed several medications -- including Percocet and Valium -- leading up to her plastic surgery. Michele's doctor said he did not usually prescribe those medications, but did so because Martin, who was a physician, asked him to.

Following the surgery, Somers went to her parents' home to take care of Michele, but Martin told her to leave, the documents state. When Somers returned, she reportedly found her mother unresponsive. The documents state that Somers confronted her father, who said he may have overdosed Michele. The documents later describe this overdose as a "practice run," and quote Michele as saying "if something happens to me, make sure it wasn't your dad."

But despite the overdose, Michele reportedly began to recover over the next several days. Before a week had passed, the documents state, she called Somers and said Martin had been treating her well. She also mentioned that she was going to pick up her 6-year-old daughter, Ada, after school.

That same morning, Martin reportedly called Alexis and said Michele was not getting out of bed or listening to him. The documents say Alexis thought the call was strange. Later that day, Martin picked up Ada, who was surprised because she believed Michele was coming to get her, according to the documents.

When Martin and Ada arrived at their home, Martin allegedly sent his daughter to check on Michele. Ada found Michele unresponsive and sitting up in the bathtub, according to the documents, and went to get Martin. Martin allegedly responded very slowly.

Martin also eventually gave an account of finding Michele that conflicted with Ada's and a neighbor who came to help, according to the documents. He reportedly said that Michele was face down in the water and must have slipped, while Ada and the neighbor said Michele was sitting up. Doctors later found evidence to corroborate Ada's account.

The documents state that both before and after Michele's surgery, Martin and Willis frequently communicated via text message. Martin also allegedly had his son's girlfriend flush Michele's medication down the toilet, but told Somers the police had taken it. He also allegedly was "flippant" about being a bachelor again, and according to the documents said the autopsy needed to be completed so he "would not be implicated in Michele's death." The documents describe this statement as an "odd remark" from someone who would have been grieving.

Eventually, doctors found several drugs in Michele's system. Though these drugs were not lethal by themselves, the combination reportedly could have stopped Michele's heart "because of the additive effect." The documents make a point of stating that Martin requested that Michele take the drugs, and that he had the capacity to kill his wife. Somers also reportedly told authorities that her mother would not have taken the drugs on her own because she was sensitive to medication.

The documents also state that MacNeill made numerous statements that were "inconsistent with the facts surrounding the death of his wife."

Prosecutor Chad Grunander said Friday he could not comment on the investigation. But Somers said she was relieved more information about the case was becoming public. Somers and other MacNeill family members have been working for three years to prove their father killed their mother, and she said she hopes the search warrant produces more evidence about what happened.

"I know that my dad and Gypsy had been in very close contact, and I'm assuming there will be more information," she said of the search warrant.

Somers described the case as horrifying, saying that her father sent her 6-year-old sister to find her dead mother. Somers did not know when official charges might be filed, but said there is still more information about the case that hasn't been made public.

"There's a lot of evidence and there's a lot of information that's still not out," she said.

MacNeill currently is serving a federal prison sentence for making false and inconsistent statements, insurance fraud and forgery. Gypsy Willis recently completed a prison sentence for her conviction on federal identity theft charges, and is awaiting sentencing on state identity theft charges.