The Murder of Alex Pennig: What the Locked Bathroom Door Revealed

In the early hours of December 16, 2022, 32-year-old nurse Alexandra Pennig, known to family and friends as Alex, was found with a gunshot wound inside the bathroom of her downtown St. Paul apartment. The man who called 911, fellow nurse practitioner Matthew Ecker, told police that Alex had taken his gun, locked herself in the bathroom, and died by suicide.

But almost immediately, detectives saw details that did not fit his account. Alex was right-handed, but the gun was positioned beneath her left hand. The gun and her hand appeared unusually clean, even though the fatal wound was a close-contact gunshot. Matthew, who said he had tried to stop Alex's bleeding before calling for help, had no blood on his clothing or hands. The bathroom sink where he said he washed up was dry.

The Door Lock Beneath Alex's Head

After Alex's body was moved, crime scene investigators found a small ring of metal beneath her head. It had broken off the bathroom door lock and was covered in blood. Prosecutors argued that this detail showed the door had been forced open before Alex was shot, not afterward as Matthew had claimed. Alex's body was also positioned in a way that would have kept the door from closing.

Matthew Ecker's Changing Story

Matthew admitted he moved the gun after the shooting. He first said he picked it up and placed it on Alex's chest. Later, he told investigators that he had actually hidden the gun in his suitcase before returning it to the bathroom and placing it beneath Alex's hand. Matthew said he panicked because the gun was his, but detectives believed he had tried to make the death look self-inflicted.

A Case Built on Circumstantial Evidence

The medical examiner classified Alex's manner of death as undetermined because the autopsy alone could not conclusively identify suicide or homicide. At trial, the state presented the physical evidence, Matthew's contradictory statements, and the timeline between the couple returning to the building and his 911 call. The defense argued that Alex died by suicide and that Matthew made terrible decisions afterward because he was in shock.

On February 16, 2024, a jury found Matthew guilty of second-degree intentional murder. He was sentenced to 30 years in prison. In April 2025, the Minnesota Court of Appeals affirmed his conviction, finding that the evidence supported the jury's conclusion that Matthew intentionally killed Alex.

We cover Alex's life, the complicated relationship at the center of the case, the physical evidence inside the apartment, and the trial that followed.

Sources:

1. Alexandra PENNIG Obituary (2023) - Lindstrom, MN - Pioneer Press

2. State of Minnesota, Respondent, vs. Matthew Phillip Ecker, Appellant

3. The Strange Shooting of Alex Pennig | Full Episode + Post Mortem

4. Matthew Ecker Murder Sentence Longer Than Expected | Fergus Now

5. Fergus Falls Man Charged with 2nd Degree Murder in St Paul

6. Staged Suicide | Matthew Ecker Interrogation

7. A Minnesota woman is fatally shot in her bathroom. Who pulled the trigger? - CBS News

8. How a small piece of a bathroom door lock helped solve the murder of a Minnesota nurse - CBS News

9. Where is Matthew Ecker’s Family Now?

10. https://coms.doc.state.mn.us/publicviewer/OffenderDetails/Index/268547/Search

11. Tracking the hours before a young Minnesota woman became a murder victim - CBS News

12. ER practitioner gets 30 years for murdering girlfriend, staging suicide in her downtown St. Paul apartment