How DNA Evidence Solved the 26-Year-Old Murders of Robin Cornell and Lisa Story

The continual advancement of forensic DNA analysis has allowed investigators to pry open the crypt on cases long sealed shut. Whether it’s the exoneration of the Central Park Five or the 2020 arrest of Joseph DeAngelo for the Golden State Killer murders that terrorized California in the ‘70s and ‘80s, forensic DNA allows police officers (and defense attorneys) to suddenly catch up to inconvertible truth that had previously seemed forever elusive.

Perhaps nowhere is this more evident than the case of the 1990 rape and murder of 11-year-old Robin Cornell and her 32-year-old babysitter, Lisa Story, in Cape Coral, Fla. It was a crime scene so brutal that police officers wept. And one with no real leads … until one day in 2016, when it was suddenly open-and-shut.

The case received extensive national media exposure; it was featured multiple times on America’s Most Wanted to jog attention from the public. The victims’ faces were put onto prison playing cards to draw leads from other inmates. But for over 20 years, the Cape Coral Police Department couldn’t get any traction, leaving loved ones, including Robin’s mother, Jan Cornell, heartbroken in their grief, enraged about the lack of justice and terrified by the thought of a murderer still on the loose.

On May 10, 1990, at around 11 p.m., Jan left home to spend time with her then-boyfriend (and later husband), Donnie Battista. Robin, a fifth grader, wanted to have a sleepover with a friend, but Jan refused because Robin had not cleaned her room. Jan’s best friend, Story, who had just moved in two days prior, was home that night and playing babysitter for the few hours Jan was away.

Battista only lived a few blocks away from the home, so Jan’s plan had been to watch a football game with him and then come home in the late night so she could wake up there for her morning shift. However, she fell asleep on the couch, waking up around 4 a.m. in a panic about not making it to work on time. She rushed home to iron her nurse uniform only to discover a horrific scene. 

The door wasn’t locked the way she had left it, and when when she looked at her ironing board, she saw that someone had moved framed pictures of Robin and Story onto it.

Jan went upstairs and discovered Robin in her room, naked and strangled to death with her own undergarments. Story had also been raped and killed, but Jan didn’t know that until police officers, responding to the scene, told her later.

Cape Coral police officers were able to retrieve viable sperm cell DNA samples at the scene, but there were no matches.

Several early leads in the case dead-ended quickly. In 1994, the Cape Coral Police Department briefly looked into Frank Thaniel Potts, a migrant worker who was arrested that spring for murder in Alabama after skeletal remains were found at his cabin in the woods. But Potts was quickly ruled out when his blood type turned out to be type A; the double murder in Cape Coral had been committed by someone who was type O. 

Investigators looked at others, like serial killer Donald Leroy Evans, but ties were similarly weak. 

Then suddenly, in 2016, the case broke open.

In August 2016, 54-year-old Joseph Zieler and his 25-year-old son, Zachary, got into a heated argument in the town of North Fort Myers, Fla. Enraged, Joseph shot Zachary with a pellet gun. After Zachary was rushed to the hospital for emergency surgery, police arrested Zieler for felony aggravated assault.

A 2009 Florida state law requires felony defendants to submit their DNA into a state database even if they have not been convicted of a crime. When Zieler’s was submitted, the DNA analysis showed an overwhelming overlap with the sperm cells from the double murder. It was a level of match that could be expected in one in 83 quintillion people. 

In a recorded jailhouse conversation, Zieler told his wife to pack her bags for a quick escape. 

However, that escape would never happen. Zieler was charged with two counts of first-degree murder, two counts of sexual battery and burglary. 

At trial, Zieler maintained his innocence and asserted that his DNA could’ve been at the scene if he’d had consensual sex with either of the adult women in the home, though Jan adamantly denied the idea. Zieler also said that he had been arrested and was jailed in Maryland at the time of the killings; the state of Maryland said they had no record in support of that alibi.

The jury convicted Zieler on all charges. 

In a 10-2 vote, Zieler’s jury voted to give him the death penalty. Afterwards, Jan told reporters, “I felt like I needed to be [Robin and Story’s] voice and I wasn’t going to let either one of them down.” 

In a press release, Florida’s Attorney General called Zieler a “depraved criminal,” adding that “he will never see the outside of a prison cell again.”

In the courtroom, after his appeal for a new trial was denied, Zieler elbowed his attorney Kevin Shirley in the face. 

“I used to box, I’ve taken a lot better shots than that,” Shirley told the court, later saying in an emailed statement to NBC News that, “It was probably his last effort to put on a public display and I was the only civilian that he was able to lure within arms reach.”