Minnesota’s best known cold-case consultant helps grieving families get justice

Sheila Potocnik cried into her phone, gasping for breath. When her brother picked up, she wailed, “Jeffrey, I’m so, so sorry."

It was late on Sept. 10, 2015, when Potocnik learned that her brother’s son, 15-year-old Antonio DeMeules, had been killed by a hit-and-run driver in Isanti, Minn., while skateboarding along a two-lane road.

“His ankle is totally crushed, and his face is all road rash. And his arms, oh God,” her brother stammered.

As he trailed off, Potocnik asked a question that might be expected of Minnesota’s best known independent cold-case investigator: “Did they find who did it?”

The following day, authorities did, in fact, find the driver who killed Antonio, who claimed he thought he’d hit an animal. That story stuck, for a time. Until Potocnik discovered critical evidence investigators had overlooked, which sent the driver to jail.

Getting justice for Antonio was the first high-profile case Potocnik cracked as a private consultant specializing in criminal case reviews and supporting victims as they navigate the criminal justice system. She’s one of the rare independent investigators taking on this meticulous, emotionally taxing work — the need for which is staggering.

Since the mid-1960s, Minnesota has accumulated more than 2,000 unsolved homicides, along with an untallied number of suspicious deaths. While law enforcement has only so many resources, the digital era has made it easier for civilians to revisit cold cases. These private sector sleuths range from freewheeling armchair detectives to credentialed investigators such as Potocnik, and some of their efforts have sparked controversy.

But several of Potocnik’s clients say they consider her an invaluable lifeline, after they’ve spent years, if not decades, suffering from ambiguous loss and lack of closure. They’re wracked not only by the grief of a death, but also by not knowing what, exactly, happened to their loved one. And whether someone was at fault.

“Sheila is here to give me another opinion on my broken heart,” said Patty Brunn, who asked Potocnik to look into the death of her 23-year-old son, Joseph Brunn, presumed to have drowned in the Mississippi River a decade ago, after drinking at an Otsego, Minn., bar. Like many clients, Brunn sought Potocnik both for her professional expertise and her empathy, knowing she was a fellow mother who would understand the depth of her loss.

Potocnik knows all too well the pain of experiencing a loved one’s traumatic death. And Antonio’s killing wasn’t the first time her family had lived the nightmare.

Growing up in south Minneapolis, Potocnik and her older sister Laura DeMeules were inseparable.

As a high-schooler, DeMeules developed a drug addiction that led to lawbreaking, Potocnik says. But she remained a bubbly, happy presence and had been working to get her life on a better track.

On Nov. 6, 2005, 33-year-old DeMeules was found beaten and strangled to death along a gravel road near Northfield. A man had been driving his backhoe to a neighbor’s when he spotted her naked body at the edge of a field.

The Rice County sheriff investigated, along with the Bureau of Criminal Apprehension (BCA) and Minneapolis police. Potocnik put up a billboard seeking tips near the home off East Lake Street where DeMeules was last seen. She knocked on doors and handed out flyers.

Throughout the investigation, Potocnik was grateful for Rice County Sheriff Sgt. Dave Stensrud’s responsiveness and compassion. He even sent the family notes and cards on DeMeules' birthday and holidays.

Nearly two years after DeMeules' murder, Stensrud called Potocnik with shocking news: “We’ve got him.”

Minneapolis police had picked up a man named Antonio Medina for drunken driving. When his profile was submitted to the Combined DNA Index System (CODIS), it matched a sample collected from DeMeules’ fingernails.

Stensrud’s call flooded Potocnik with emotions: elation, sadness, hate. Her sense of vengeance was entwined with a vocational calling. “It inspired me to want to bring that same sense of justice and relief to others who are still waiting for answers,” she recalled.

Although Potocnik went on to earn a law enforcement degree and has additional training in forensic pathology and digital forensics, she considers her sister’s case file her seminal playbook.

Medina pleaded guilty to second-degree murder with intent and went to prison.

Nearly two decades later, with Medina slated for release in May, Potocnik tries to focus on the good her sister’s death produced. “Laura wanted me to help all of these families,” she said. “And then in turn, so did Antonio.”

While Potocnik views her sister’s case as textbook police work, she considers her nephew Antonio’s the opposite.

When the family met with the Isanti County Sheriff’s Department, Potocnik felt officers blamed the crash on Antonio, painting him as a reckless teen who had been wearing dark clothing and skating in the middle of the road. “My gut told me something is not right here.” (The sheriff and deputy sheriff at the time are no longer with the department and either did not respond to or declined a request for comment.)

Authorities released surveillance video images of the truck that hit Antonio. The next day, its driver, Adam Maki, turned himself in, claiming he thought he’d hit a dog or a turkey. The Isanti County sheriff described the crash as a “terrible accident.” Case closed.

Weeks later, the pain of Antonio’s death was compounded by what Potocnik discovered in his file. She scrutinized each piece of the investigation, calling witnesses to fact-check reports and conducting additional research. Potocnik found gaps, inconsistencies and new information suggesting that Maki was more culpable than he let on.

Among the issues were discrepancies about Antonio’s location and visibility. Maki’s vehicle hadn’t been thoroughly inspected. Potocnik also learned that just before he hit Antonio, Maki had been drinking at a bar.

Potocnik’s most damning discovery was that the sheriff’s office didn’t analyze the report from the forensic extraction of Maki’s phone. The information was delivered on Blu-Ray technology, which the department didn’t have.

When Potocnik opened the report, she saw that Maki, who told officers he wasn’t on his phone, had sent several texts during his drive. In fact, he was likely on a call at the moment of the collision.

The log also showed that less than an hour after the crash, Maki searched for an Isanti County scanner, used to listen to police dispatch calls. Why would someone who thought he’d hit an animal do that? Potocnik asked the sheriff’s department. With this new evidence, Isanti reopened the case, and Maki was convicted of leaving an accident scene.

Potocnik says that absorbing the details of Antonio’s violent end was gut-wrenching, but she felt responsible for getting her nephew the respect he deserved. “You almost have to try to disassociate yourself, as family,” she said of viewing his autopsy photos. “But you want justice, so you’re like, who else is going to speak for them, besides me?”

“CSI” and other popular crime shows portray law enforcement officers practically racing from investigating a crime scene to arresting a perpetrator. Potocnik says this has given the public an unrealistic expectation about how quickly and seamlessly cases can be resolved — and how many cases go unsolved.

Sixty years ago, law enforcement solved about 90% of U.S. homicide cases. Since then, the clearance rate has declined to roughly 50%. A broad range of factors can make it more difficult for officers to clear cases, from the prevalence of firearms to inadequate staffing and training, particularly in the realm of digital forensics.

While the extra data available from social media and cellphones can help solve cases, it can also bog down investigations, says Prof. Ashlyn Kuersten, who oversees the Cold Case Program at Western Michigan University. Leads can be buried in a haystack of irrelevant information that law enforcement isn’t staffed to sift through, she said, comparing a 700-page case file from the 1980s with a 70,000-page file from a present-day case.

Kuersten and other cold case experts say that getting fresh eyes on cases can be extremely valuable. But enlisting citizen sleuths has its risks, as unethical operators have harassed persons of interest and spread false information and could potentially take advantage of victims. But Kuersten acknowledges that law enforcement officers aren’t infallible, either. And when that happens, victims often have no idea.

Most people have never seen a police report and don’t know their rights to information, says Michael Lewandowski, a former homicide investigator and licensed private investigator based near St. Cloud. Lewandowski, who has worked with Potocnik on several cases, says the two of them can be useful liaisons for victims because they know how the system works. And their credentials get the attention of overwhelmed or unresponsive agencies.

But investigators from the private sector walk a “fine line” in their relationship with their government counterparts, says Lewandowski, who respects his former peers in law enforcement. “You need them to send you the reports and things like that, but you’re also finding mistakes that they’ve made, frankly,” he said.

Potocnik says she’s not afraid to challenge law enforcement when she has strong evidence. At the same time, she says she holds the profession in high regard and emphasizes their shared goal: “to seek the truth and hold individuals accountable if a crime has been committed.”

Lewandowski says it’s rare for investigators to have both the stomach for viewing disturbing photos or bodycam footage and the capacity to earn trauma victims’ trust. “A lot of guys with law enforcement background don’t want to get involved in that kind of stuff,” he said.

Potocnik only takes on a fraction of potential clients, a majority of whom are women who say she was the first person who listened to their questions about their loved one’s case.

Some clients — a rape victim, to use a recent example — simply seek reassurance that their case was thoroughly investigated and want an advocate to guide them through their interactions with authorities.

Clients express immense gratitude for Potocnik’s tactical and emotional support. Many refer to her as “a voice for the voiceless” and even “an angel.” That’s whether Potocnik concludes the original investigation was solid, or, as was the case of a young man from Rogers poisoned by fentanyl, she finds information that helps spur an arrest.

Last May, Potocnik stood beside that young man’s mother and placed a hand on her back as she addressed a packed Minneapolis courtroom.

“He stole my son’s yesterday, today and tomorrow,” Jean Thurmer said of Michael Harlan, seated nearby in an orange jumpsuit. Harlan was being sentenced for murdering Thurmer’s son, Cole Linnell, whose 29 years flashed by in a slide show: kid in a pumpkin costume, high schooler in sports uniform, young adult gathering with family.

Linnell was a gifted athlete, but he’d been dogged by a leg injury that curtailed his college baseball career. Linnell had endured multiple surgeries and was prescribed oxycodone, the narcotic pain reliever, at 14 years old, Thurmer said.

On March 14, 2021, Linnell was found dead in his Rogers home. The coroner’s report cited mixed ethanol and fentanyl toxicity. For months, Thurmer says she heard nothing from law enforcement about their investigation.

Frustrated, Thurmer turned to Potocnik. While Rogers police had told Thurmer they weren’t able to track Linnell’s whereabouts later on the day of his death, Potocnik assisted with tracing his digital trail, which suggested he’d met up with someone named “Eric” to purchase “blues” (a street term for oxycodone) in St. Paul. The pills were actually fentanyl, a far more toxic drug.

Rogers police Capt. Jason Foster said electronic evidence that Potocnik shared about Linnell’s connection to “Eric,” an alias used by Harlan, “jump started” their investigation, which eventually led to Harlan’s arrest. Potocnik then supported Thurmer through a jarring turn of events: Harlan fled the courthouse during his trial and spent nine months on the run before being apprehended by the FBI.

Thurmer says she felt Potocnik treated Linnell as if he were one of her own three sons. And that she is beyond grateful to know what happened to him. “I don’t have to walk through the rest of my life not knowing,” Thurmer said.

Potocnik has not yet been able to give Sandra Cikotte Anderson that same sense of resolution about the death of her son, Robert Anderson, who died at age 19, in 2009.

For years, Potocnik has been trying to shed light on the suspicious circumstances of the December night Anderson was hanging out with two friends at a home in Maple Grove, watching movies, playing video games and drinking.

Around 3:30 a.m., Anderson’s friends called 911 and reported that he’d stopped breathing. Officers arrived to find that Anderson’s face was not only blue but battered and bruised, as if he’d been in a fight. The Hennepin County Medical Examiner listed Anderson’s cause of death as “unexplained.”

When Potocnik reviewed the case, she found plenty to suggest foul play — including a videotaped confession. She helped get Anderson’s body exhumed and, after a second autopsy, two independent pathologists determined his manner of death was homicide.

The police have twice brought the case to the Hennepin County Attorney’s Office, which has twice declined to press charges. But Cikotte Anderson says she will continue to try to push her son’s case forward. “I’ll go to my grave, trying until my deathbed,” she said.

She says she never could have persisted in her quest for truth without Potocnik’s support. “I’m indebted to her for the rest of my life.”