Prosecutors said Pedro Grajales planned the 2023 killing of Nilda Rivera before driving her body to police headquarters and confessing.

HARTFORD, Conn. — A local man received a 30 year prison sentence after admitting he stabbed his girlfriend to death inside his car in 2023, a killing investigators said he planned in advance before driving to police headquarters with the victim still in the passenger seat.

Pedro Grajales, 55, received the sentence in Hartford after a case that stretched from an April 16, 2023, killing to a murder plea in December 2025 and sentencing in February 2026. The case drew wide attention because of the details described in court records: prosecutors said Grajales treated Nilda Rivera kindly so she would not suspect an attack, bought her food at a Hartford McDonald’s, then drove to a nearby lot and stabbed her more than 25 times. The sentence closed the criminal case, but it also renewed focus on the planning, the violence of the attack and the loss described by Rivera’s family.

Authorities said the final hours began with what looked like an ordinary outing. Rivera, 57, of New Britain, got into Grajales’ car on April 16, 2023, after he had already hidden a knife in his pants pocket, according to the arrest warrant. Investigators said he drove her to a McDonald’s on Brainard Road in Hartford, went through the drive-thru and let her eat in the parking lot before leaving for a more secluded area nearby. Court papers said Grajales later told police he had been planning to kill Rivera for several days because he believed she had cheated on him. To avoid raising suspicion, the warrant said, he was “treating her very nice” before the attack. Prosecutors said he then pretended he was stopping to pick up lumber, shifted in the driver’s seat, and set up the assault inside the car.

The arrest warrant described the attack in blunt terms. Investigators said Grajales moved his seat back to create room, pulled the knife from his left pocket and repeatedly stabbed Rivera while she sat in the front passenger seat. Police later said she suffered wounds to her chest, head, face and arms. Officers who rushed to the car outside Hartford police headquarters found Rivera unresponsive and covered in blood, with a knife in the center console, according to police accounts released after the arrest. They tried life-saving measures until emergency crews arrived, and Rivera was taken to St. Francis Hospital, where she was pronounced dead. The warrant said Grajales told police he watched Rivera gasp for air and waited for her to die before driving to the station. Investigators also said he showed officers photographs of Rivera’s body on his cellphone after walking into the lobby and reporting the killing.

The first public account of the case came just after 3:20 p.m. that Sunday, when police said Grajales entered the Hartford Police Department and told the front desk he had stabbed his girlfriend. Officers went outside and found Rivera in the car parked in front of the building. Early reports identified Grajales as 52 at the time of the arrest; by the time of sentencing nearly three years later, he was 55. Police Lt. Aaron Boisvert said after the arrest that Grajales appeared covered in blood when he came into the station. The location of the stabbing, investigators later determined, was in the Murphy Road area. The basic sequence of events never changed: an apparent domestic dispute fueled by jealousy, a deadly attack inside the vehicle, and a confession delivered minutes later at police headquarters. What remains less clear from the public record is whether there had been any immediate confrontation in the car before the stabbing began or whether Rivera had any warning at all in the final moments before the attack.

Rivera’s family gave a very different picture of the relationship than the calm trip to get food might have suggested. Her daughters told local television reporters in the days after the killing that Grajales was possessive and controlling. One daughter said he was “very jealous” and went through Rivera’s phone and social media accounts, deleting messages and removing people. Another described Rivera as a woman “just looking for love.” The family’s comments placed the homicide in a broader pattern often seen in domestic violence killings, where jealousy and control become central facts in the investigation and later in sentencing. Public reports also said Grajales had 15 prior convictions dating to 1994, including burglary, drug and larceny offenses. Those earlier convictions were not the basis of the murder charge, but they added to the portrait prosecutors presented of a defendant with a long criminal history before the killing of Rivera.

The legal path moved slowly after the arrest. Hartford police charged Grajales with murder in April 2023, and he was held on high bond as the case moved through Superior Court. Public reports indicate that the case did not end in a full trial. Instead, Grajales admitted guilt in December 2025, avoiding a jury verdict on the murder count. Court records reviewed by news outlets showed that he was sentenced on Feb. 18, 2026, to 30 years in prison. Some reports described the December proceeding as a guilty plea; others said he was found guilty in December before sentencing in February. What is clear from the available court reporting is that the murder case was resolved by late 2025 and the sentence was imposed the following February. No public report reviewed here described additional charges beyond murder, and no appeal or post-sentencing filing had been detailed in those reports as of March 18, 2026.

By the time of sentencing, the case had become as much about the details of planning as about the confession itself. Investigators said Grajales did not lash out in a sudden argument at the police station or during a public dispute in the restaurant parking lot. Instead, the court papers described a series of deliberate acts: hiding the knife before picking Rivera up, taking her to get food, waiting while she ate, driving to a secluded lot, pretending to stop for lumber and then attacking in close quarters inside the car. Those details gave prosecutors a narrative of premeditation and gave Rivera’s family a painful timeline to revisit in public. The sentence of 30 years means the criminal punishment is set, but it does not answer every question the case raised, including how long Rivera had been trying to leave the relationship or whether other people close to her had seen signs that the danger was rising in the days before she was killed.

The personal toll stayed at the center of the public reaction. Rivera’s daughters spoke publicly after the killing from the family kitchen where, they said, she had recently celebrated a birthday. Their grief sharpened the contrast between the routine details of the day and its ending: a meal from a chain restaurant, a ride in a familiar car, and then a fatal attack carried out by someone she knew. One daughter said Rivera “didn’t deserve to die.” Another remembered her as a mother, grandmother and friend. Those short statements gave the case its clearest human frame. In court and in police documents, Rivera appeared as a victim in a murder file. In her family’s words, she was also a woman with children, grandchildren and a place at the center of a household that was left to absorb the shock of a killing that prosecutors said was planned days in advance.

The case now stands closed at the trial-court level with Grajales sentenced to 30 years in prison for Rivera’s killing. Unless new motions or an appeal are filed, the next milestone is any routine post-conviction action in Connecticut court records rather than another public hearing on the facts of Rivera’s death.