The family of a man who was killed by his cellmate while in custody of the Denver Sheriff’s Department has filed a federal lawsuit against the city.

Angela Hernandez, the mother of Vincent Chacon, joined civil rights attorneys Mari Newman, Andy McNulty and Madeline Leibin on Monday outside the Denver Downtown Detention Center to announce the filing, highlight what they claim are systemic failures and seek “transparency and accountability.”

“Today, I’m not just asking for answers. I’m demanding them, and I’m asking for transparency. I’m asking for accountability,” Hernandez told reporters.

The lawsuit was filed Sunday and names the City and County of Denver, Denver Sheriff Elias Diggins and eight additional DSD employees as defendants.

A spokesperson for the City Attorney’s Office told The Denver Gazette that it “doesn’t have a comment to share at this time,” adding that it has not yet been served with the complaint.

According to court documents, Chacon was booked into DDC on June 26, 2025, on a failure-to-appear warrant issued by the Lone Tree Police Department for alleged shoplifting, with bail set at $750.

On June 30, 2025, deputies responded to an overnight call for help in the Downtown Detention Center where Chacon was being held.

They found 34-year-old Chacon unresponsive in his cell, where he was pronounced dead, police said in a news release. Police investigators later said the red marks found on his neck were consistent with manual strangulation.

Though Chacon had arrests on his criminal record for aggravated robbery, car theft, felony menacing and drugs — his cellmate, a 38-year-old man named Ricky Roybal-Smith, should never have been put into that cell with him, Hernandez told The Denver Gazette.

Roybal-Smith “tried to tell deputies my son choked on an apple,” she said.

Detention center deputies found Chacon on his lower bunk that night, covered to his neck in a blanket, according to an affidavit for Roybal-Smith’s arrest.

Denver Police Det. Keith Lewis arrived at the scene around 4:20 a.m., finding red marks on Chacon’s neck and discoloration in his eyes that he determined were more consistent with manual strangulation than choking on a foreign object.

Roybal-Smith, in April, pleaded guilty to the 2025 death of Chacon.

As part of the plea deal, Roybal-Smith was sentenced to 48 years in prison.

The sentence is to be served concurrently – not consecutively – with the 80-year sentence he received last month for homicides in Aurora. 

Roybal-Smith pleaded guilty to two counts of second-degree murder for the stabbing deaths of Scott Davenport and Jesse Shafer. The two victims were killed in separate stabbings the morning of June 29, 2025.

Roybal-Smith was on parole at the time of the killings. Chacon was killed hours after Roybal-Smith was arrested in connection with a hit-and-run crash. 

Denver Gazette reporter Michael Braithwaite and 9News contributed to this story.