On June 7, 1993, John Kowalczyk was found murdered in a parking lot in Milwaukee.

This unfortunate event sparked a long and complex investigation that traversed three states, resulting in multiple suspicious deaths being linked to the initial case. 

Investigation Discovery’s ‘Nightmare Next Door: Everyone Has a Motive‘ details the trial of Ralph Shambaugh Jr., accused of the murder, who faced prosecution in the absence of sound evidence due to the highly circumstantial nature of the case. 

Viewers are provided an insight into what transpired after John’s murder through phone and bank records that were used by the prosecution to make their connections.

However, with so many loose ends, what really happened? 

John Kowalczyk murder

John was a prominent figure in his community. He immigrated with his family from Poland to New York at a young age and worked for the Defense Intelligence Agency before moving into real estate. 

Since 1979 he had been married to Katherine Hyman, and the couple had two sons, which they raised in Vienna, Virginia. 

In 1993 a great tragedy occurred; John and Katherine were going through an unpleasant divorce at the time, which had affected their visitation rights with their two children. 

On June 10 of that year, John drove into an office parking lot with his son Nicholas, who was just 12 years old.

It was approximately 8 PM, and they were awaiting Katherine’s arrival to take Nicholas home.

Nicholas was in the middle of a scenic voyage along with his father, John, when they stopped to discard some trash.

Out of nowhere, devastating deathly silence interrupted the atmosphere as Nicholas heard a gunshot. 

The gunshot had dealt a fatal blow to his father, who slumped in the seat behind him with a 30-caliber sabot round entering from behind his right ear. 

Recognizing that his father was no longer alive, Nicholas looked around in shock, yet could not locate the menacing figure responsible for this horrendous crime.

Who killed John Kowalczyk?

The investigation into John’s untimely death was a knotty one right from the start.

Just before his death, records showed that he had suffered mounting financial hardship due to bankruptcy and was dealing with the aftermath of a bitter divorce case against his ex-wife, Katherine. 

On June 11, John was due in court to ask for increased visitation rights with his two sons.

It all began two years ago when Katherine found out about John’s liaison with Lisa Zumwalt and ended their marriage. 

Additionally, there was much animosity between Lisa and her former husband, James Zumwalt, inducing authorities to include James as a possible suspect in the crime due to motive. 

Determining who killed John would require sifting through layers and layers of complex detail.

After investigating James, the police shifted their focus to Stanley Hyman.

It was public knowledge that he had paid for both his daughter Katherine’s divorce from John and the subsequent legal proceedings. 

Given this animosity and contact between them, it made sense that John could potentially see Stanley as a threat.

Subsequently, when a similar gun to the murder weapon was found in their home in McLean, Virginia, it appeared to be an open-and-shut case. 

However, after further investigation, it was eventually confirmed that it wasn’t, in fact, the murder weapon and that Stanley and his wife had provided an alibi at the time of John’s death. 

This was further bolstered by a missing person case in West Virginia which seemed to point suspicion away from Stanley Hyman but failed to come up with a concrete answer in regards to who actually committed this heinous crime.

The mysterious disappearance of James Alting, a maintenance worker at the same resort where Stanley and his wife were regular visitors, sparked more investigations into the investigation of John’s murder. 

Stanley reported an attack by a man that matched Alting’s description. Consequently, when police searched his room, they found a paper with Stanley’s phone number and a matchbook from a motel in Vienna. 

The leads obtained related to Alting’s case led to Ralph Shambaugh Jr., who had previously talked to Stanley. With these connections in mind, authorities theorized that Stanley may have hired Ralph to kill John while Alting served as the getaway driver.

As the police investigation continued, it led to two resort workers in connection with John Alting’s murder.

Then, in another shocking twist, Alting was found dead in a well on a property owned by Ralph’s family that summer. 

Furthermore, just one month later, Stanley and his wife were found dead in an apparent murder-suicide in a rented Florida home.

The couple wrote a short suicide note claiming they had nothing to do with John’s murder. 

This tragic event ended the investigation and left many questions unanswered about what really happened on that hot summer day in 1993 when John died.