A Hartford man was sentenced to 30 years in prison after prosecutors said he took his girlfriend to McDonald’s for a final meal, drove her to a secluded parking lot and stabbed her more than 25 times inside his car before bringing her body to a police station to confess.
The case, which began with an April 2023 killing and ended with a February 2026 sentencing, drew attention for its reported planning and for the way the suspect described what he did to investigators. Authorities said Pedro Grajales believed his girlfriend, Nilda Rivera, had been unfaithful and decided to kill her. After his arrest, police and family members described a relationship marked by jealousy and control, while court proceedings later focused on the violence of the attack and Grajales’ prior criminal record.
Grajales, 55, pleaded guilty to murder in December 2025, and a judge sentenced him on Feb. 18 to 30 years in prison, according to court records cited in reports. Rivera was 57 and lived in the New Britain area, authorities said. Police and court filings said the fatal stabbing happened on April 16, 2023, after the couple made a stop at a McDonald’s on Brainard Road in Hartford and then drove to another lot nearby. Investigators said Grajales hid a knife in his pants pocket before he picked Rivera up that day and acted unusually kind to keep her from suspecting his plan.
In a probable cause affidavit and arrest warrant described in media accounts, Grajales told detectives he had been planning to murder Rivera for several days. Police wrote that he drove through the McDonald’s drive-thru, then parked so Rivera could eat in the lot. Afterward, he took her to a secluded area and pretended he was searching for discarded lumber for a home renovation project. Investigators said he shifted in the driver’s seat, moved it back to create space, and then pulled the knife and began stabbing Rivera as she sat in the front passenger seat. The warrant said he stabbed her repeatedly, striking her in the chest, head, face and arms.
The attack did not end at the parking lot, police said, because Grajales then drove directly to the Hartford Police Department. Investigators described him as covered in blood when he entered the building and told staff at the front desk that he had stabbed his girlfriend and that her body was in the car outside. Police said he showed an officer a photo on his cellphone of a woman with multiple stab wounds, then directed officers to the vehicle. First responders tried lifesaving measures once they found Rivera in the front seat, but authorities said she died within minutes. Court filings described a knife in the car as well, and police treated the death as a homicide caused by the stabbing injuries.
Rivera’s death quickly spread beyond Hartford because of the details in the early reports, including the confession at the police station and the claim that the killing was fueled by suspicion of an affair. Investigators said Grajales blamed Rivera’s relationship with another man and, at times, suggested that other people should bear responsibility for what happened. Police also said the evidence showed planning rather than a sudden fight. The affidavit said Grajales watched Rivera struggle to breathe and waited for her to die before driving to the station, a detail that became central to the public retelling of the case.
Family members described Rivera as a mother and grandmother who tried to find stability and affection, and they said they saw warning signs in the relationship. One of Rivera’s daughters, Daniella Valle, said her mother was “just looking for love” and described her as a friend and a caregiver whose life ended without reason. Another daughter, Yaitza Casanova, described Grajales as intensely jealous and said he would look through Rivera’s phone and remove contacts and social media connections. Those accounts added a portrait of a relationship with controlling behavior that relatives said escalated before the killing.
The case also carried the weight of Grajales’ criminal history, which surfaced in court and in coverage of the sentencing. Reports said the court noted he had about 15 prior convictions dating back to the mid-1990s, including burglary and other drug and larceny cases. That record shaped how the case unfolded from the start, including bail decisions. After his arrest, a judge set bond at $3 million, and the case moved through the court system over the next two years as prosecutors prepared for trial and the defense weighed possible resolutions.
The legal path ended in a guilty plea rather than a jury verdict. Grajales pleaded guilty to murder in December 2025, court records cited in reports said. That plea resolved the core criminal charge and set the stage for a sentencing hearing in February 2026. At sentencing, the judge imposed a 30-year prison term. Reports did not indicate that the court announced additional prison time beyond the murder sentence, but the record included references to his earlier convictions. Officials and relatives also spoke about Rivera’s life and the impact of her death, which they said left a lasting hole in their family.
Investigators continued to rely on documentation created in the earliest hours after the killing, including the warrant written after Grajales arrived at the police department and gave statements to officers. That document captured the steps police said he described, from the McDonald’s stop to the secluded lot and the confession at the station. The warrant and affidavit also recorded the extent of Rivera’s wounds and the statements Grajales made about why he did it. Prosecutors did not publicly detail every piece of evidence that would have been used at trial, but the confession, physical evidence in the vehicle, and medical findings formed the backbone of the case as described in public filings.
The killing also spurred community grief and renewed attention to domestic violence and lethal relationship control, even as investigators focused on specific criminal proof. In the days after Rivera died, relatives spoke publicly about what they felt were missed signs and a pattern of jealousy that they said should have been taken seriously. They described Rivera’s daily role in their lives and said they struggled with the idea that she shared a meal and normal conversation shortly before the attack. Friends and family said they hoped the court process would bring accountability for her death and recognition of who she was beyond the details of her final day.
In court, the central questions shifted from what happened to how the system would punish it. By the time of the plea and sentence, the case record already included the claim that Grajales planned the killing for days, hid a knife in his pocket, and used deception to keep Rivera calm. Prosecutors typically treat premeditation and attempts to conceal intent as aggravating facts, even when a formal plea avoids a full trial. The defense did not publicly outline a competing account of the killing in the reports that summarized the case, but the guilty plea removed any dispute over whether Grajales caused Rivera’s death.
With sentencing complete, the remaining milestones involve corrections processing and any potential post-conviction filings. State prisoners can seek review on limited grounds after a guilty plea, though courts often uphold plea agreements when the record shows they were entered knowingly and voluntarily. No public report indicated that Grajales filed an appeal immediately after sentencing. For Rivera’s family, the court decision closed the criminal case while leaving the larger work of grieving and remembering her, as they continued to describe her as a mother, grandmother and friend whose death they said should never have happened.
As of Wednesday, Feb. 25, Grajales was serving the 30-year sentence imposed on Feb. 18, and officials had not announced any change to the disposition of the case. The next update is expected only if court records reflect a post-sentencing motion or an appeal filing in the months ahead.
Author note: Last updated February 25, 2026.