William Costello, accused serial rapist, ends his trial by killing himself

In November 2012, we told you about the arrest of William Costello, a successful real estate broker with powerful political ties, on accusations of serial rape -- and the next month, he was linked to two more sex assaults.

This week, prosecutors finally began laying out their case against Costello, only to have a mistrial declared -- because Costello had apparently committed suicide. See photos, video and details below.

As we reported, the rape accusations against Costello, 49 -- a broker for Denver's Unique Properties with a reputation as a good father and ties to influential Democrats such as Colorado Governor Dick Lamm -- began with a very different crime.

On June 30, 2012, according to the first in a series of arrest affidavits on view below, a Denver Police rep was called to the King Soopers at 2810 Quebec Street on an assault report. There, the officer learned that an elderly man had been standing near the door collecting signatures for a pro-life petition. When he asked a customer to sign the sheet on his clipboard, the man, later identified as Costello, rejected this entreaty because of his belief in abortion. However, Costello is also said to have shouted several obscenities -- and when the petition collector told him he could "still go to heaven," he supposedly became even more exorcised, grabbing the clipboard in order to throw it to the ground and pushing him off his bike.

The fall broke the man's hip.

At that point, Costello fled the scene -- but a witness eyeballed his license plate, allowing the cops to track him down. When confronted, Costello is quoted as claiming that while angry words had been exchanged, he'd only grabbed the clipboard to prevent himself from being struck by it and denied that he'd given the man a shove. Instead, he insisted that the man had toppled of his own accord.

The officer didn't buy this explanation and arrested Costello on suspicion of second-degree assault of an at-risk adult.

The bust triggered the collection of a DNA sample -- and when personnel checked it against previously collected data, matches were reportedly found in a three separate cases.

The first incident took place in March 2008 and involved a thirteen-year-old girl who lived at the Denver Children's Home. She told an officer that she'd become upset with the personnel at the facility and had decided to run away. Shortly after reaching the intersection of East 16th Avenue and North Bellaire Street, she was approached by a dark blue, four-door sedan driven by a five-feet-ten-inch, 160 pound white male with short brown hair and blue eyes.

The man, who wore a black baseball cap, a red T-shirt and green shorts, was accompanied by a two-year-old boy in the back of the vehicle. He told the girl his name was Will, and asked if she wanted to hang out. She agreed and climbed into the vehicle, at which point he began to touch and penetrate her genitals. This went on for five minutes or so, after which the man told her he'd ejaculated.

He then told her he wanted to do it again, and she complied, reportedly because she feared for her safety -- and she had every reason to be afraid. Before he let her go, she said he opened his trunk and pulled out a black, semi-automatic handgun.

Continue to read more about the death of accused serial rapist William Costello, including photos, video and original documents.

KEEP WESTWORD FREE... Since we started Westword, it has been defined as the free, independent voice of Denver, and we'd like to keep it that way. With local media under siege, it's more important than ever for us to rally support behind funding our local journalism. You can help by participating in our "I Support" program, allowing us to keep offering readers access to our incisive coverage of local news, food and culture with no paywalls.
Michael Roberts has written for Westword since October 1990, serving stints as music editor and media columnist. He currently covers everything from breaking news and politics to sports and stories that defy categorization.
Contact: Michael Roberts

Latest Stories