Diego Santoy

Case overview

Diego Santoy Riveroll was a Mexican university student who was accused of stabbing his ex-girlfriend, Érika Peña Coss, and killing her two young siblings in the City of Monterrey on March 2, 2006. He was sentenced to 138 years in prison on October 11, 2011.

Timeline

• March 2, 2006 — Érika Peña Coss woke up early in the morning and found Santoy inside the house wearing a mask; she said he silenced her and started beating her with a hammer, told her he had already killed her two little siblings, and said the servant was about to die from a drug overdose; she said he later asked her to stab him, then threatened to kill her and commit suicide; she stated he proceeded to stab her in the neck and the back.
• March 7, 2006 — Santoy was captured by police at a roadblock in Oaxaca.
• Four days later (from the end of Santoy’s capture described as four days after) — Santoy was captured by police at Oaxaca, where he was found in a bus along with his brother.
• After a few weeks in prison — Santoy retracted his confession, stating that he was forced by officers to make up the whole story.
• October 11, 2011 — Santoy was sentenced to 138 years in prison.

Background

Érika Peña Coss had broken up with Diego for personal reasons, but she said he kept calling and seeking her because he was unable to accept the relationship ending. Santoy was described as angry because his former girlfriend ended their relationship.

Santoy confronted the whole Peña family, the servant, and the secretary during a trial in January 2007, and during the confrontations it was made public many of the above statements on the family lifestyle. Santoy once again accused Érika of being the killer and asked her family to tell the truth about the case.

Rumours around the case included claims that Teresa Coss had engaged in sexual relationships with influent people, including Aldo Fasci, Assistant State Prosecutor.

Santoy had gained notoriety due to high levels of media interest in the case and the even higher rarity of the case. He was nicknamed “el asesino de Cumbres” (the murderer of Cumbres), with Cumbres being the area of Monterrey where the killings happened.

The offence

On March 2, 2006, Érika Peña Coss said she found Santoy inside the house wearing a mask. She said he silenced her and started beating her with a hammer in the parietal. She said he told her he had already killed her two little siblings and that the servant was about to die from a drug overdose.

Érika said Santoy laid by her side and claimed he wanted to die next to her, but after thirty minutes nothing happened. She said Santoy asked her to stab him, which she refused to do. She said Santoy then threatened to kill her and then commit suicide to “catch up” with her. She said he proceeded to stab her in the neck and the back. Érika said she was almost dead when Santoy left.

She said that later it was stated that her injuries were severe and required a six hour surgery to save her life. She said that while badly hurt she crawled to the office in the back of her house and asked the secretary to call for an ambulance. She said that Santoy had indeed killed her younger siblings and had badly beaten the servant.

The account also described a lapse of five hours during which Azura, one of Érika’s older sisters, assured she didn’t know what was going on. It was stated that it had been proved that if all of the above statements had happened, she would have heard something.

Santoy’s account disputed parts of Érika’s story. His version pointed Érika as the killer. According to Diego, he had a sexual encounter with Erika’s mother. He also claimed that Erika’s father offered him and his daughters marijuana. Another statement he mentioned was that he was sure the killed children were of another father. It was also stated that accusations and rumours involving abortion and family fights were made to accuse Érika as his accomplice.

In Santoy’s confession, Érika was described as wanting to kill her siblings in order to take revenge on her mother and because of material matters, since they were born to a multimillionaire, owner of a television company. Santoy said Érika called him a day before and asked him to meet at her house at 4:00AM. Santoy said that once there, Érika asked him for help to exact revenge upon her mother by killing her younger siblings. Santoy said he described to the authorities the way she stabbed her little brother and asphyxiated her sister with a rope. Santoy said that after that, they made a “suicidal pact” which was violated by both.

Érika was also alleged to have asked Diego to kill her, kidnap the servant who was locked in the bathroom at the moment, and kill himself by throwing both himself and said servant from the Puente Atirantado. Santoy’s narrative included that he tried to hit her in the head with a hammer but didn’t the courage to hit her hard enough. He said that he then “stabbed” her and was about to do what she told him. It was described that he then declared he lacked the courage to kill the servant and released her from her imprisonment and even gave her change to take a bus.

Investigation and arrest

Santoy was captured by police. The narrative described his capture by police on March 7, 2006, at a roadblock in Oaxaca. The narrative also described that four days later Santoy was captured by the police at Oaxaca, where he was found in a bus along with his brother.

Confession, retraction, and competing accounts

While imprisoned, Santoy confessed to the murders, confirming Érika’s story. However, after a few weeks he retracted the confession, stating that he was forced by the officers to make up the whole story. Santoy’s retracted version of the murders pointed Érika as the killer.

Trial

In January 2007, Santoy confronted the whole Pena family, the servant and the secretary during a trial. During those confrontations it was made public many of the above statements on the family life-style.

The Peña Coss family still denied the allegations and insisted it was Diego who killed the children. Many local Santoy supporters gathered outside the prison, claiming he was innocent and denouncing Érika.

Inconsistencies and disputes described in the case narrative

It was stated that at the very beginning of the case Santoy was seen as the sole suspect, but then the focus of the media changed to include the Peña Coss family too.

The narrative described that people commented on the case and said that in a case in which a surviving victim had a relationship with the aggressor, the reaction would be feeling angry against the aggressor. It said this was the Peña family’s current position.

The narrative stated that statements made by the Peña family, including:

• “Diego was crazy because of the stars”
• “I saw it all coming and warned Erika; 'This boy is going to kill you'” were described as “weren’t quite helpful,” and it said none of them had been seen as “trustworthy” in any interviews since they often contradicted each other, especially the exact time of the crime.

It was stated that Érika had changed her allegations about when she woke up on the day of the crime, with earlier claims that she woke up at 7:30AM and later declarations that it was at 12:00PM.

It was also stated that both Érika and the servant claimed to have seen Diego holding a gun and having a mask covering his face, and that neither the gun, the mask nor the actual weapons used had been found. The narrative stated that it was assumed that an injury inflicted by a hammer should have been able to kill someone, and that someone cold enough to kill two defenseless children should be able to kill the source of the rage.

The narrative described conflicting accounts involving the secretary:

• Érika was said to have first stated that she “crawled” into her office, which was located in her house, where the secretary worked for Teresa Coss, and pleaded her to call an ambulance.
• Diego’s declaration was described as that he offered Érika to call an ambulance while he was unsuccessfully trying to kill her.
• The secretary’s account was described as that Érika came “normally walking into her office” and “casually asked her to call an ambulance” and waited for its arrival by her side, telling her supposed details on what had happened.

The narrative also stated it was suspicious that Érika was already out of the hospital only thirteen days after the crime was committed.

Outcome

Diego Santoy was sentenced to 138 years in prison on October 11, 2011.