Newly revealed jail calls involving Mackenzie Shirilla are drawing major attention after recordings allegedly captured her speaking in a secret coded language with her mother, Natalie Shirilla, while behind bars.

According to recordings obtained by PEOPLE, Mackenzie would suddenly switch into gibberish-style speech during phone conversations whenever sensitive topics came up — especially when other inmates were nearby or within earshot. The coded language reportedly inserted “ezza” sounds into words and syllables to disguise what was being said.

In one call, Mackenzie allegedly used the secret language while discussing a man she had been communicating with in jail. In another, she switched into code after mentioning that her cellmate was present in the room. The conversations reportedly became difficult even for her own mother to understand at times, forcing Natalie to stop and ask her daughter to repeat herself.

What makes the calls even more controversial is that prosecutors previously decoded portions of the language during Mackenzie’s murder trial and used it as evidence in court.

Investigators claimed one decoded statement allegedly involved Mackenzie asking her mother if they could tell police she had suffered a seizure following the deadly 2022 crash — something prosecutors argued showed an attempt to cover up what they believed was an intentional act.

The case shocked the country after prosecutors accused Mackenzie of deliberately crashing her vehicle into a building at over 100 mph in Strongsville, Ohio, killing her boyfriend Dominic Russo and friend Davion Flanagan.

At trial, prosecutors described the crash as a failed murder-suicide attempt tied to relationship problems, while the defense argued Mackenzie suffered a medical episode related to POTS and blacked out behind the wheel.

Mackenzie was ultimately convicted on multiple charges, including murder, aggravated vehicular homicide, and felonious assault. She is currently serving concurrent sentences of 15 years to life at the Ohio Reformatory for Women and will become eligible for parole in 2037.

Interest in the case has surged again following the release of the The Crash documentary on Netflix, which revisits the fatal crash and the legal battle that followed.