Pregnant Mistress Refused to Get an Abortion. Then She Was Killed and Her Home Burned Down to Cover Up Crime: Complaint By Chris Spargo

A college professor in Wisconsin is charged with homicide after the woman with whom he had carried on a years-long-affair was found dead in her apartment.

Alexis Pickett, 27, was declared dead on the scene after officials responded to a fire at her residence on Nov. 13 in La Crosse. A dog was also found deceased at the scene.

Following an autopsy, the medical examiner ruled Pickett’s death a homicide and said that she had been killed before the blaze, according to a copy of the criminal complaint obtained by PEOPLE.

Matthew Sierra, the married man who confessed to police that he was having an affair with Pickett, is now accused of killing both her and their unborn child.

La Crosse County Sheriff’s Deputy Jordan Stratman wrote in the complaint that an investigator spoke with Pickett’s friend after her death, who alleged that Sierra was not happy about the pregnancy.

The friend told investigators that Pickett and Sierra were already the parents to a son, who had been staying at her home on the night of his mother’s death, according to the complaint.

“All I know is that they have been on and off and they have been constantly fighting because he found out she was pregnant with his kid and he didn’t want anything to do with it,” the friend told police.

She then “indicated” that Sierra “wanted [Pickett] to have an abortion but [Pickett] did not want to do that,” according to the complaint.

The friend also told the investigator that Sierra allegedly threatened to take full custody of the couple’s child if Pickett did not terminate the pregnancy, per the complaint.

Pickett, meanwhile, had already announced the news on Facebook, writing: “Me and [my son] forever. New addition coming soon. [My son’s] going to be a big bro.”

In a separate interview, Sierra’s wife told police that she was aware her husband was in an extramarital affair with Pickett and had fathered a child outside their relationship, according to the complaint.

She did not have any contact with her husband’s mistress though, and the complaint stated that she told police Pickett had been blocked on her phone because “she made it a point to never see or communicate with [her] because she had to spend a bunch of money on extra therapy that basically hypnotized her to not think about [Sierra] and [Pickett] having sex.”

The wife added that she feared “all that would go down the crapper” if she ever saw Pickett in person, according to the complaint.

She did tell police, however, that she believed Sierra was home on the night of Pickett’s death and did not see him leave the house at any point.

Sierra’s phone was also at his residence at the time of Pickett’s killing and the fire, according to investigators.

But surveillance footage revealed that Sierra was not only at Pickett’s home on the night of her murder but also left just as the fire started to spread through the residence, the complaint alleges.

Sierra did not immediately flee from the scene but instead drove a short distance and stayed there until multiple smoke alarms could be heard going off inside Pickett’s apartment building, per a timeline assembled by police in the complaint, based on surveillance video.

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Sierra was arrested on Dec. 17, shortly after Dr. Michelle Stram and her staff at the Southeast Minnesota Regional Medical Examiner’s Office determined that Pickett was “deceased prior to the fire” based on the lack of soot in her lungs and carbon monoxide in her blood stream, according to the complaint.

He is charged with first-degree intentional homicide, first-degree intentional homicide of an unborn child, arson and mistreatment of animals for allegedly killing Pickett’s dog.

Sierra will appear in court on Dec. 23. He has not yet entered a plea, but records show his lawyer filed a motion to dismiss, which was denied by the judge.

Sierra’s attorney did not respond to a request for comment.