Conviction October 5, 2012 Homicide

Jessica Ridgeway

Ten-year-old Jessica Ridgeway was abducted while walking to school in Westminster, Colorado, on October 5, 2012. Her dismembered remains were found days later in Arvada. Austin Sigg, then 17, was arrested after his mother called police; prosecuted as an adult, he pleaded guilty and was sentenced in November 2013 to life in prison plus 86 years.

Status
Conviction
Type
Homicide
Date
October 5, 2012
Location
Westminster, Colorado
Age
10
Gender
Female
Decade
2010s
Where the case stands
  1. Open
  2. Partly resolved
  3. Charges or trial
  4. ClosedConviction

At least one person was convicted in connection with the case.

Timeline to scale
Each dot is a dated event below; the distance between dots is elapsed time. The darker dot marks the incident.
May 28, 2012: Austin Sigg, 17, attempts to abduct a 22-year-old woman jogging near Ketner Lake in Westminster; she escapes and reports the assault, but the case initially goes unsolved.October 5, 2012: Jessica Ridgeway, 10, disappears while walking to Witt Elementary School in Westminster, Colorado; her mother is notified of the absence that afternoon and contacts police.October 7, 2012: Jessica's backpack, water bottle, and eyeglasses are found in Superior, Colorado, about six miles from her home, indicating an abduction.October 10, 2012: Remains later identified as Jessica are discovered in Pattridge Park Open Space near Arvada; the case is classified as a homicide.October 23, 2012: Sigg's mother, Mindy Sigg, calls 911 to report that her son confessed to the killing.October 24, 2012: Austin Sigg is arrested at his Westminster home in connection with Jessica's abduction and murder.October 1, 2013: Sigg pleads guilty in Jefferson County District Court to all counts, including first-degree murder, kidnapping, sexual assault, and sexual exploitation of a child.November 19, 2013: Judge Stephen Munsinger sentences Sigg to life in prison with parole eligibility after 40 years on the murder count, plus an additional 86 years for the remaining charges.20122013
Colorado
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On the morning of October 5, 2012, 10-year-old Jessica Ridgeway left her home in Westminster, Colorado, to walk to Witt Elementary School, a route that took her toward a neighborhood park where she typically met other children. She never arrived at school. When the school notified her mother that afternoon that Jessica had been absent, the family alerted authorities, and a large-scale search quickly began across the Denver metropolitan area.

Early signs pointed to an abduction. On October 7, investigators recovered Jessica's backpack, water bottle, and eyeglasses roughly six miles from her home in Superior, Colorado. The discovery intensified fears for her safety and drew hundreds of volunteers, local police, and the FBI into the search. On October 10, 2012, human remains later identified as Jessica were found in Pattridge Park Open Space near Arvada, about nine miles from where she had disappeared. Authorities disclosed that the body had been dismembered, and the case was formally classified as a homicide.

The investigation led police to Austin Reed Sigg, a 17-year-old resident of Westminster who lived near the park where the backpack items had been found. On October 23, 2012, Sigg's mother, Mindy Sigg, called 911 to report that her son had confessed to the killing. Officers arrested Sigg at the family home that night, into the early hours of October 24. Investigators also connected Sigg to an earlier attack: on May 28, 2012, he had attempted to abduct a 22-year-old woman who was jogging near the same lake; she fought him off and reported the assault, though the case had remained unsolved at the time.

Because Sigg was under 18 at the time of the offenses, prosecutors charged him as an adult but could not seek the death penalty. On October 1, 2013, in Jefferson County District Court, Sigg pleaded guilty to all charges against him, a total of about 15 counts including first-degree murder, second-degree kidnapping, sexual assault, attempted kidnapping, and sexual exploitation of a child. During the proceedings he acknowledged responsibility for luring, killing, and dismembering Jessica.

On November 19, 2013, District Judge Stephen Munsinger sentenced Sigg. For the first-degree murder count, committed as a juvenile, he received life in prison with the possibility of parole after 40 years, reflecting U.S. Supreme Court limits on mandatory life-without-parole sentences for juveniles. The judge then imposed an additional 86 years for the remaining counts, to be served consecutively, effectively ensuring Sigg would spend the rest of his life incarcerated. Sigg remains in the custody of the Colorado Department of Corrections. The case, which shook the Denver suburbs and prompted widespread discussion of child safety, is considered closed with a conviction.

childjuvenile offender
  1. May 28, 2012
    Austin Sigg, 17, attempts to abduct a 22-year-old woman jogging near Ketner Lake in Westminster; she escapes and reports the assault, but the case initially goes unsolved.
  2. October 5, 2012
    Jessica Ridgeway, 10, disappears while walking to Witt Elementary School in Westminster, Colorado; her mother is notified of the absence that afternoon and contacts police.
  3. October 7, 2012
    Jessica's backpack, water bottle, and eyeglasses are found in Superior, Colorado, about six miles from her home, indicating an abduction.
  4. October 10, 2012
    Remains later identified as Jessica are discovered in Pattridge Park Open Space near Arvada; the case is classified as a homicide.
  5. October 23, 2012
    Sigg's mother, Mindy Sigg, calls 911 to report that her son confessed to the killing.
  6. October 24, 2012
    Austin Sigg is arrested at his Westminster home in connection with Jessica's abduction and murder.
  7. October 1, 2013
    Sigg pleads guilty in Jefferson County District Court to all counts, including first-degree murder, kidnapping, sexual assault, and sexual exploitation of a child.
  8. November 19, 2013
    Judge Stephen Munsinger sentences Sigg to life in prison with parole eligibility after 40 years on the murder count, plus an additional 86 years for the remaining charges.

About this entry

This case is recorded as conviction and is kept in the index for its historical and investigative significance. At least one person was convicted in connection with the case.

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Entry last updated November 4, 2026.

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{{cite web |url=https://coldcaseindex.com/cases/jessica-ridgeway/ |title=Jessica Ridgeway |website=ColdCaseIndex |date=2026-11-04 |access-date=}}