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The County of DuPage
Wheaton, Illinois

Press Release

Monday, January 4, 2021

Appellate Court Affirms 90-Year Sentence in 1993 Double Homicide

DuPage County State’s Attorney Robert B. Berlin announced today that the Second District Appellate Court of Illinois has affirmed the ninety-year sentence of Sean Helgesen for the 1993 murders of Peter and Diana Robles.

On April 17, 1993, Helgesen and Eric Robles, the victims’ son, arrived at the Robles home. Once inside the home, the pair stabbed and slashed Peter twenty-two times in the face, neck, chest and arms in a downstairs washroom. Helgesen and Robles then went to the main floor of the home where they encountered Diana, on crutches, and proceeded to stab and slash her twenty-nine times in the face, neck chest and arms. Peter died at the home while Diana died a short time later at a local hospital. Following the murders, the pair left the home.

In 1995, a jury found Helgesen, who was seventeen years-old at the time, guilty on ten counts of murder, He was sentenced to natural life in prison. Following a Supreme Court decision in Miller v. Alabama in 2012, which prohibited mandatory sentences of natural life without the possibility of parole for juveniles, Judge George Bakalis resentenced Helgesen to serve two ninety-year sentences concurrently. In resentencing Helgesen, Bakalis stated “the overriding consideration in my mind was the offense itself, seriousness of the offense, the nature of the offense. I know it’s a severe sentence. It’s a very severe crime.” Helgesen appealed this sentence, arguing that the sentences were unconstitutional amounting to a de facto life sentence. The Appellate Court however, disagreed with Helgesen’s assertions holding that the sentences were extended-term sentences and were justified by the fact that Diana was physically handicapped, which is an extended-term-qualifying factor. In its decision, the Appellate Court noted that Courts are not prohibited from sentencing a juvenile to a life sentence, either natural or de facto, and may do so if “the trial court determines that the defendant’s conduct showed irretrievable depravity, permanent incorrigibility or irreparable corruption beyond the possibility of rehabilitation.”

“I would like to thank the Appellate Court for their thorough analysis of this case and their finding that the sentences imposed are indeed appropriate,” Berlin said. “The brutal, pre-meditated murder of Peter and Diana Robles is among the worst crimes DuPage County has ever had to endure and shook the entire community to its core, the reverberations of which can still be felt today. The Appellate Court’s decision ensures that Mr. Helgesen will be held accountable for his actions to the fullest extent of the law.”

Justice Hutchinson delivered the judgment of the Court with Presiding Justice Bridges and Justice Zenoff concurring.

Due to sentencing guidelines in place at the time, Helgesen is required to serve 50% of his sentence.

Helgesen’s appeal was defended by Lisa Hoffman of the DuPage County State’s Attorney’s Criminal Appeals Division.