“Deadly Obsession”: Dateline Reports on Mike Sisco & Karen Harkness Homicides April 4 2025

This Friday, April 4, 2025, Dateline NBC will air a new episode titled “Deadly Obsession” at 9:00 PM ET/8:00 PM CT. The episode takes viewers into the haunting and protracted case of Dana Chandler, convicted earlier this year for the 2002 murders of her ex-husband, Mike Sisco, and his fiancée, Karen Harkness. Set in Topeka, Kansas, the case has captured national attention for more than two decades, marked by cold leads, overturned convictions, and questions about justice.

Correspondent Andrea Canning reports on the saga that has unfolded since Sisco and Harkness were discovered shot to death in Harkness’s home. Chandler’s trial history includes three separate proceedings, one overturned conviction, a hung jury, and finally, a third conviction in 2025. The episode investigates the long search for answers and the emotional toll on the families of the victims, bringing audiences face to face with one of Kansas’s most enduring criminal cases.

A Double Homicide in Topeka Sends Shockwaves Through the Community

On July 7, 2002, Mike Sisco and Karen Harkness were found dead in the basement bedroom of Harkness’s Topeka duplex. The couple, returning from an evening at a local casino, had planned to host family for a fish fry that afternoon. When they failed to show, family members entered the home and discovered the pair had been shot multiple times while in bed.

There was no evidence of forced entry or robbery. Eleven shell casings were recovered from the scene, and both victims had been shot with a 9mm weapon. Investigators found no conclusive physical evidence pointing to a suspect. However, they began focusing on Dana Chandler, Sisco’s ex-wife, due to what they described as obsessive behavior and a volatile relationship history.

An Investigation That Went Cold — Until the Media Sparked New Interest

Although suspicion surrounded Chandler early on, the case remained unsolved for years due to a lack of concrete forensic evidence. Chandler, who had been living in Denver, provided credit card receipts as an alibi and denied any involvement. Investigators pointed to gaps in her financial and phone records but lacked enough to make an arrest.

The cold case gained new momentum in 2009, when CBS’s 48 Hours aired an episode highlighting the unsolved murders. The national attention prompted Shawnee County’s new district attorney, Chad Taylor, to reexamine the evidence. Chandler was arrested in 2011 and charged with two counts of first-degree murder.

A Controversial Conviction and a Disgraced Prosecutor

In 2012, Chandler was convicted and sentenced to life in prison. The prosecution, led by Assistant District Attorney Jacqie Spradling, leaned heavily on circumstantial evidence, pointing to Chandler’s alleged obsession with Sisco and a pattern of controlling behavior. Chandler’s children, including her daughter Hailey, testified against her.

Years later, the Kansas Supreme Court overturned Chandler’s conviction after finding that Spradling had engaged in misconduct, including presenting false and misleading evidence to the jury. The court described her actions as an “intolerable pattern of deception,” and Spradling was disbarred in 2021. Chandler’s conviction was vacated, and she was transferred from state prison to the Shawnee County Jail, awaiting a new trial.

Second Trial Ends in a Hung Jury, But Prosecutors Press Forward

In 2022, Chandler faced her second trial. The prosecution maintained their theory of motive based on jealousy and long-standing resentment. They introduced evidence such as hundreds of phone calls Chandler made to Sisco and Harkness in the months before the murder. However, the defense argued that no forensic evidence placed her in Kansas at the time of the crime.

The jury deliberated for six days but failed to reach a unanimous verdict. The foreman revealed that seven jurors supported conviction while five held out. A mistrial was declared, and prosecutors began preparing for a third trial. Chandler’s defense argued that the prosecution suffered from tunnel vision and ignored other viable leads.

Third Trial Results in a Conviction After More Than 20 Years

In early 2025, Chandler stood trial for a third time. This time, a Pottawatomie County jury found her guilty after 4.5 hours of deliberation. The trial featured over 60 witnesses and testimony about Chandler’s mental health history, including a 1998 diagnosis of histrionic personality disorder and depression. Prosecutors focused on her behavior leading up to the murders, including breaking into Sisco’s home and making repeated phone calls.

The defense continued to emphasize the lack of physical evidence and framed Chandler as the victim of investigative bias. Still, the jury convicted her of two counts of first-degree murder. She is scheduled to be sentenced on June 2, 2025.

The Role of the Media and Public Interest in a Long-Running Case

Media coverage played a crucial role in this case’s evolution. From the original 48 Hours broadcast in 2009 to renewed coverage by CBS and now NBC’s Dateline, the public’s interest in the Chandler case has remained high. Legal analysts have often pointed to this case as an example of how media attention can reignite investigations and shape public perception.

Supporters of Chandler have raised concerns about her conviction, with the nonprofit Miracle of Innocence funding her defense. Others, including members of the victims’ families, expressed relief at the final verdict. The case continues to spark debates about justice, prosecutorial ethics, and the reliability of circumstantial evidence.

A Final Verdict After Decades of Uncertainty

After years of legal setbacks, mistrials, and appeals, Dana Chandler’s conviction in 2025 brings closure for some, though questions remain for others. With sentencing scheduled for June and further appeals likely, the case may not be entirely over.

Still, the latest verdict marks a turning point in one of Kansas’s most notorious murder cases. Dateline NBC’s “Deadly Obsession” brings the full story to television, chronicling not only a tragic double homicide but also the long, complex road to justice.