A Denver District judge Wednesday sentenced the youngest teenager charged for the 2020 arson in Green Valley Ranch that killed five members of a family to seven years in Colorado’s Youthful Offender System, part of the Department of Corrections, and an additional three years in the Division of Youth Services.
Dillon Siebert, now 17, pleaded guilty to second-degree murder. His name has not previously been published because his case proceeded in juvenile court. Siebert was 14 at the time of the fire in August 2020.
In a Wednesday hearing in Denver District Court, attorneys indicated he will face a 10-year sentence total. He had a sentencing in juvenile court at 1 p.m. Wednesday, where he was sentenced to three-years in the Division of Youth Services, according to a news release from the Denver District Attorney's Office. The juvenile hearing was not open to the public.
The sentence took into consideration his minimal role in planning the fire, attorneys said.
Siebert is one of three teenagers charged for intentionally setting fire to a home on Truckee Street Aug. 5, 2020. The blaze killed five members of a Senegalese family: Djibril Diol, 29, Adja Diol, 23, their daughter, Khadija, just under 2, Hassan Diol, 25, and her 7-month-old daughter, Hawa Beye.
Three others escaped the burning house and survived.
The teens told investigators they intended to get revenge for a robbery now-18-year-old Kevin Bui had been the victim of weeks before the deadly fire. He used an app to track his stolen phone to what he thought was the address of the alleged assailants. But they targeted the wrong house.
Siebert will turn 18 in October, according to court records.
Bui and Gavin Semour, now also 18, face dozens of charges, including premeditated first-degree murder. Prosecutors charged them as adults since they were both 16 at the time. Their cases are still ongoing.
Family members and friends of the victims expressed disappointment with Siebert’s sentence in emotional statements. The deaths forever destroyed their families and changed the West African immigrant community here, they said.
“They killed me. I’m dead since August 5 of 2020,” said Amadou Beye, Hassan Diol’s wife and Hawa’s father.
He wore a white sweatshirt with a photograph of his wife and daughter. He only ever met his daughter over video chat because he came to Colorado later than her and his wife. Beye said it hasn’t been easy to face Siebert, but he plans to keep showing up to court in the cases of the other two teens in hopes of getting justice.
“For me, my life doesn’t make sense anymore.”
Part of the heartbreak suffered, friends and family members said, is that the victims represent the American dream of seeking to build a new life for themselves and their families.
“You cannot dream if you cannot sleep in peace," said Amadou Dieng, a friend of Djibril Diol. He said the fire spurred other immigrant families in Green Valley Ranch to add security cameras to their homes because they feared being targeted next.
"The only thing you might have is a nightmare.”
Siebert’s defense attorney and guardian ad litem painted him as deeply remorseful, and emphasized they didn’t intend to minimize his actions.
Judge Martin Egelhoff nodded as public defender Johnna Stuart acknowledged it remains “perplexing” that the crime was committed by children.
Stuart said Siebert latched onto friendships to define his identity and get support from a young age — spurred by bullying and isolation because of a developmental delay in his speech. Depression drove him to start drinking.
She also suggested his reliance on social attachments explains why Siebert did not try to stop the act or tell anyone afterward.
“His biggest fear was social rejection,” she said.
Siebert started spending time with Bui and Seymour in the summer of 2020, Stuart said, attracted to them because of their popularity at school and their status as football players.
Stuart said the night of the fire, Siebert had just lost his grandmother. He drank heavily to cope, and asked his best friend to hang out, but he wasn’t available. So Siebert turned to Seymour and Bui instead, she said.
If he had gone with his other friend that day, “No one would know who Dillon is. But because he went with them that night, he participated in what ended up being this horrific tragedy.”
Amadou Beye left the courtroom at one point, overcome with emotion as Stuart gave her statements.
Siebert apologized in a short address to the court. He asked the victims’ family members – and the victims themselves – for forgiveness.
“I pray to them all the time hoping they will forgive me, and I would do anything for it,” he said.
Stuart suggested Siebert wasn’t aware ahead of time the two older teens planned to set fire to the home. The vast majority of social media messages between the three were exchanged only between Seymour and Bui, she said, and messages about revenge Siebert was included on in the days leading up discussed childish ideas, such as egging the house or planting smoke bombs.
Prosecutor Courtney Johnston confirmed Siebert had little involvement in planning the act, though she said he should not escape accountability for participating in setting the fire and leaving the people in the house to die.
But she acknowledged he did not appear to carry on a normal life after the crime as Seymour and Bui appeared to.
“That may seem like a small thing," Johnston said, "but we’re looking globally in thinking about how to handle a case.”
Johnston said both sides agreed a 10-year sentence is appropriate, but acknowledged it provides little comfort to surviving victims and family members.
“Ten years is never going to be enough when you consider the loss here,” she said.
Siebert shows a strong desire to atone for his actions, his advocates said. Stuart also said he has gotten good grades while incarcerated, has plans to finish high school this year and wants to go to college.
Egelhoff said even after decades on the bench, he was at a loss to offer anything that could provide comfort to the victims’ families and friends. He showed deference to the attorneys’ decision that Siebert’s sentence was appropriate, but recognized it would not console the families.
In accepting the plea, he told Siebert: “Earn this. You’ve been given an extraordinary chance to feel a consequence, but also be in a position to … earn some level of redemption.”