'My daughter was murdered in school - it took me 10 years but I solved case'

A night of celebration quickly turned into a nightmare for a family of five in 2015. It was the evening of a graduation ceremony held by a prestigious private school, celebrating eldest daughter Samira’s completion of high school.

Thousands of guests filled the school’s gymnasium, including family, friends and colleagues of Beatriz’s father, Sandro, an English teacher at the institution. Just hours later, seven-year-old Beatriz Angélica Mota would be found dead inside her own school.

During the event, Beatriz asked her mother, Lucinha Mota, for permission to get a drink of water from a nearby drinking fountain. The area was familiar - it was both the children’s school and the father’s workplace.

Around 30 minutes later, after noticing the child’s absence and failing to locate her, Sandro went on stage and briefly interrupted the performances to call for his daughter.

The search began immediately, with guests and staff joining in. At around 11pm, Beatriz’s body was found inside a deactivated sports apparel storage room near the gym.

She had been stabbed 10 times, and the knife used in the attack was found close to her body.

Forensic experts later determined Beatriz had not been killed in the room where she was found. The absence of traces there indicated she had been murdered elsewhere and then hidden - which made sense as the room itself had become largely inaccessible to students in recent years.

In the early stages of the investigation, witnesses reported seeing a man wearing a green shirt lingering near the drinking fountains shortly before Beatriz disappeared. Police also confirmed a set of keys granting access to multiple areas of the school had gone missing days earlier. Security cameras around the campus were found to have been compromised, with critical footage deleted.

As the months passed with no resolution, Beatriz’s father publicly accused law enforcement of obstructing the investigation, citing information uncovered by a private investigator hired by the family: “In our parallel investigation, we discovered things we would rather not even talk about. There has been a certain misuse of authority. We are discovering that some officers who took part in Beatriz’s investigation, in one way or another, hindered the process,” he said in a radio interview.

Throughout the years, Lucinha Mota began to apply public pressure by organising demonstrations, giving interviews, and even walking more than 430 miles over 23 days from the family’s hometown of Petrolina to the state capital, protesting outside the governor’s office.

Just two weeks after the highly publicised walk, a major breakthrough came in January 2022. DNA found on the handle of the knife used in the crime was matched to Marcelo da Silva, then 40, whose genetic profile was already stored in the state database. He was already serving a prison sentence for other crimes, including the sexual assault of a child.

Marcelo confessed on video, telling police he had entered the school intending to steal money. According to his statement, Beatriz became frightened upon seeing him and began to scream, prompting him to stab her “so she would stop screaming.”

That same night, Lucinha posted a video stating she had not been told by police about the arrest. “The police do not talk to us, so we will speak through a press conference tomorrow,” she said. The following day, she acknowledged the DNA evidence was “incontestable,” but said the alleged motive did not convince her.

In her decision to send the case to trial, Judge Elane Brandão Ribeiro highlighted forensic findings indicating possible sexual motivation. She noted abrasions on Beatriz’s body, which could suggest the crime was motivated by the child’s refusal to “consent to the accused’s sexual interests.”

Marcelo was formally charged with triple-qualified homicide - based on base motive, extreme cruelty and the use of dissimulation that prevented the victim from defending herself. His defence has repeatedly attempted to prevent the case from going to a jury trial, arguing the evidence is weak, despite his detailed confession.

Now a federal congresswoman, Lucinha Mota continues to speak publicly about her daughter’s case through podcasts, interviews and public appearances. In a recent post alongside a photo of her visiting Beatriz’s grave, she wrote: “So that we can guarantee Beatriz a fair trial, so that a jury trial can finally be scheduled - so that this monster can be punished.”