'I can't believe I did this': Boyfriend who said shooting death of girlfriend was accidental had hurt her before, police say

Left: Austin Doucette (Franklin County Sheriff's Office). Right: Mikayla Rose DeSantis (GoFundMe).

Grim new details have been revealed in a case out of Maine where a man is charged with killing his girlfriend with a bullet to her chest, according to law enforcement in the Pine Tree State.

Austin Doucette, 24, stands accused of murder over the death of 23-year-old Mikayla Rose DeSantis, according to the Maine State Police.

The underlying incident occurred at the Left Bank condominiums in Carrabassett Valley, a tiny town some 120 miles north of Portland.

On March 8, DeSantis was shot and airlifted to Maine Medical Center in Portland, where she succumbed to her injuries.

Doucette made multiple frantic and "very hysterical" 911 calls that night, police said, while initially transporting the victim in his own vehicle before meeting up with paramedics. The defendant repeatedly made exclamations about his role in the shooting, expressing shock and horror while insisting the gunfire was accidental.

"I can't believe I did this," the caller said at one point, police claim. Then, Doucette allegedly told the dying woman, "I'm sorry babe."

Now, authorities are alleging a darker side to the couple's relationship, according to search warrants obtained by the Bangor Daily News.

Both the slain woman and the defendant worked together at the Sugarloaf Mountain ski resort in Carrabassett Valley. They hailed from Connecticut and had been dating since 2018, according to law enforcement. The pair moved to Maine in 2024.

After the woman's death, multiple friends, family, and co-workers told police that Doucette had a tendency to berate and belittle DeSantis, according to the court documents.

One co-worker at the ski resort said Doucette would send DeSantis derogatory messages and threaten to put his hands on her, according to the warrants. Another co-worker described the defendant as verbally and emotionally abusive to the victim. The second co-worker also said they saw Doucette shove DeSantis twice, but that the woman had minimized those physical interactions, police said.

The second co-worker's story tracks with claims made by a manager at the ski resort who said DeSantis revealed that Doucette once grabbed her arm while she was leaving for work but that she "downplayed" the incident. In February, DeSantis allegedly asked her manager if she could work every day Doucette did not work because she did not want to be home with him, according to the warrants.

Police also allege the victim would pay off the defendant's credit card bill — leaving her with no money left over.

Another 911 call was made on the night of the incident by the defendant's father's girlfriend, Law&Crime previously reported.

During the call, the father's girlfriend allegedly said she heard the defendant reveal he was being chased by the cops, that something had happened to DeSantis, and that he was going to kill himself. Doucette's father told him not to do it, the woman said, before hanging up upon learning that the defendant had been stopped by police while she was on the line.

Inside the defendant's car, Carrabassett Valley police officers found reddish-brown stains in the back seat, along with a receipt and a cellphone, according to law enforcement. Doucette later said the phone likely belonged to DeSantis.

During a custodial interview with state police, the defendant said the victim was his girlfriend, reiterated his claim that the violence was accidental, and told police the gun involved in the shooting was still on the couch in the condo, according to charging documents obtained by Bangor-based CBS affiliate WABI. But then, Doucette invoked his right to remain silent until conferring with an attorney, police say.

A paramedic later told detectives about the original meeting with the couple, saying the boyfriend described a .45-caliber gun going off, according to an affidavit obtained by WABI.

At the second hospital, a state police detective told another investigator DeSantis was in surgery for what appeared to be a gunshot wound to the chest, but that she had lost a lot of blood and was unlikely to survive, according to the affidavit. Later, the Office of the Chief Medical Examiner performed an autopsy and ruled DeSantis's death was caused by multiple gunshot wounds, police said. Authorities later clarified to say DeSantis died from a lone gunshot wound.