WI - Professor Matthew Sierra accused of murdering pregnant mistress Alexis Pickett, setting home on fire because she wouldn't have abortion.

[Knox]

Alexis Pickett, 27, and her dog were found dead in a fire at her home on Nov. 13 in La Crosse. A criminal complaint obtained by People says video surveillance footage and cell phone data put Sierra at Pickett’s home during the time of the fire.

An autopsy determined Pickett had been killed before the fire broke out, according to the complaint.

Professor accused of murdering pregnant mistress, setting home on fire

UPDATE: Prosecutors refiled charges against Matthew Sierra, accused of murdering his pregnant mistress and setting her home on fire.

www.courttv.com

 

[Knox]

• Charges against Matthew Sierra related to the November death of pregnant Alexis Pickett and her unborn child were initially dismissed but subsequently refiled by prosecutors
• Sierra faces first-degree intentional homicide, arson, and animal mistreatment charges, with evidence including surveillance videos, autopsy results showing Pickett was deceased before the fire, and contradictory statements from Sierra
• Sierra remains held on a $1 million cash bond as court proceedings continue, with first-degree intentional homicide carrying a mandatory life sentence upon conviction in Wisconsin

Charges refiled against Matthew Sierra in pregnant woman's death, new evidence presented

The Brief

www.news8000.com

 

[Knox]

Charges were initially filed against Sierra on Dec. 17, but La Crosse Judge Scott Horne dismissed the charges after finding the criminal complaint insufficient during a Dec. 23 hearing. On Dec. 26, the La Crosse District Attorney's Office filed a new complaint against Sierra, with 14 additional pages of detail, and the case moved forward.

The basis of the charging document against Sierra, who is married to another woman, remains the same: Prosecutors say Sierra killed Pickett and burned down her home months after she told him she was pregnant with his child.

The two already shared a 2-year-old child. When Sierra attempted to persuade her to get an abortion after learning about this pregnancy, she declined.

https://www.jsonline.com/story/news/crime/2025/12/26/la-crosse-college-instructor-charged-with-murder-of-pregnant-lover/87920114007/

 

[Knox]

The amended complaint included pictures of text message conversations between the two as they argued over Pickett's pregnancy. A friend of Pickett's told authorities the two had been arguing regularly since Pickett found out she was pregnant.

"I'm going to do what I feel I need to do," a text from Sierra reads in the complaint. "You aren't going to change your mind and neither am I."

"Well tell me what are you going to do because that sounds like a threat," Pickett responded.

https://www.jsonline.com/story/news/crime/2025/12/26/la-crosse-college-instructor-charged-with-murder-of-pregnant-lover/87920114007/

 

[alexwood]

Monday, January 5, 2026 - Preliminary Hearing for Matthew Sierra

Dec. 29, 2025 article:
Charges refiled in death of pregnant La Crosse woman

From the Dec. 22, 2025 People article linked below:
"Sierra had told Pickett she needed to get an abortion prior to her death, and threatened to take custody of their son if she did not, a friend of Pickett's told investigators."

"Sierra, who is married with children, denied involvement — but surveillance footage captured him going in and out of Pickett's home on the night of her killing, according to police."

Sierra had told Pickett she needed to get an abortion prior to her death, and threatened to take custody of their son if she did not, a friend of Pickett's told investigators

Matthew Sierra (38), a Professor at a Technical College in Wisconsin (don't know whether he has been dismissed) and Alexis Pickett (27), have had an on again-off again relationship for years, and already have a 2-year-old son together. The night she was allegedly murdered, their 2-year-old son was staying with a friend of Alexis. Nonetheless, despite the fact that he is married, Matthew Sierra re-impregnated Alexis Pickett. His marriage predates his affair with Alexis Pickett. He has children he shares with his wife. His wife knew about Alexis, the affair, and the son born of that union. She apparently had no contact with Alexis, though, and did not want to have any contact with her. She was unaware of Alexis' new pregnancy. His wife "believes" that Matthew Sierra was home on the night of the (alleged) murder, and claims that she had not seen him leave the house that night. According to investigators, only his phone was at home that night -- Matthew Sierra was at (or nearby) Pickett's home between 11:30 p.m. on Nov. 12, and 3 a.m. on Nov. 13, 2025 (as alleged in the complaint).

He was not thrilled about this new pregnancy. She was 3-4 months pregnant, he wanted nothing to do with the expected baby, and threatened to take custody of their 2-year-old son if she didn't agree to have an abortion. He (allegedly) killed her and then set ablaze her second-floor apartment owned by La Crosse (WI) Public Housing Authority. Her little dog was killed in the fire. (There's an extra-special place reserved for Matthew Sierra, in my opinion.)

That's a wrap -- apparently something foreign to Matthew Sierra.

Sierra returns to State of Wisconsin Circuit Court (La Crosse County, Case No. 25-CF-1080) on Monday, January 5, 2026, at 11:00 a.m. (Central Time), for a Preliminary Hearing.

Matthew Sierra's lawyers have filed a new Motion to Dismiss, as of December 30, 2025, which they want to be heard at, or prior to, the Jan. 5, 2026 Preliminary Hearing (see above).
Lawyers file motion to dismiss in case of death of pregnant La Crosse woman