For almost four decades, the gruesome murder of three-decade-old Rhonda Marie Fisher remained unsolved, decimating her family and the investigators who suspected that multiple serial killers were at work in the Denver metropolitan area. On April 1, 1987, a motorist found Fisher’s body at the foot of an embankment near Sedalia, Colorado, with signs of sexual assault and strangulation. Serial killer private investigators know that cold cases lingered because technology was far behind the criminal appetite in 1987. Furthermore, DNA science just didn’t exist as a tool for forensics when Fisher died. In addition, important evidence (such as paper bags placed over Fisher’s hands by the coroner to retain potential trace material) went untested for decades. Therefore, this case serves as one of the best illustrations of how advanced DNA technology has allowed serial killer private investigators to solve seemingly impossible homicides years after the perpetrators die.
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The Original Investigation and Initial Dead Ends
Detectives used old-school tactics to search for Fisher’s murderer. Furthermore, investigators interviewed several acquaintances that Fisher had visited in the weeks before she died, but cleared the suspects one by one. In addition, police discussed the criminal activities of many serial offenders who were active across the Denver area from 1978 to 1988. Moreover, detectives even carried out preliminary DNA testing in 2017 with no matches. A serial killer private detective in Oklahoma City realizes that conventional methods of investigation run up against dead ends, even with the best efforts of law enforcement. But early investigators couldn’t have imagined the technological changes that would come decades later.
Vincent Darrell Groves: The Most Prolific Serial Killer in Colorado
Vincent Darrell Groves is one of Colorado’s most notorious serial murderers, responsible for at least twelve confirmed homicides between 1978 and 1988, with some 20 more victims possibly still unknown to investigators. Furthermore, Groves at the beginning looked like a high school athlete and college student with seemingly good prospects ahead of him. However, he became a vicious predator after dropping out and entering drug dealing and human trafficking. Additionally, Groves targeted vulnerable women in particular, hitchhikers and young people not under family protection. Moreover, in 1982, a court found him guilty of second-degree murder and sentenced him to a term of five years without any trial before the state released him on early parole in 1987. Tragically, Rhonda Fisher’s murder occurred in precisely the same year. A serial killer private investigator in OKC stresses that poor sentencing is sometimes what allows serial killers to claim more victims.
The Amazing Advancement in DNA
In early 2025, the Douglas County Sheriff’s Office Cold Case Unit reopened Fisher’s case decades later. Furthermore, investigators conducted an in-depth review of the available evidence and chose to test two vital items: the paper bags placed over Fisher’s hands by the initial coroner in 1987. In addition, these bags contained trace evidence—small, finite amounts of skin cells—that had been meticulously preserved for 38 years. Moreover, forensic scientist Shane Williams described the fact that the coroners in 1987 had put bags over the victims’ hands without even taking DNA analysis into account because there was no DNA science as a recognized forensic discipline. Therefore, recovering viable DNA profiles from bags that were almost forty years old proved “exceptionally rare,” according to the authorities.
The results of the DNA turned out extraordinary. Furthermore, another and very interesting case reached the investigators in late October 2025 through the national Combined DNA Index System (CODIS), a case-to-case matching system managed by the FBI. Additionally, the DNA from the paper bags matched biological evidence from three of Vincent Darrell Groves’ homicides committed in 1979. Further, Groves’ DNA remained on file from earlier convictions for those murders, allowing quick identification. A serial killer private detective in Norman discovers that centralized DNA databases allow investigators to link cold crimes with known criminals.
Critical Implications for Justice
While Vincent Darrell Groves died in Colorado Department of Corrections custody in 1996 from liver failure, without going to trial for Fisher’s murder, the DNA identification provided profound closure to her surviving family. Furthermore, Fisher’s parents and brother had died before they could get the answers, but investigators delivered the resolution to her surviving cousin. Additionally, the cousin was extremely grateful for finally getting justice and answers. Moreover, Douglas County Sheriff Darren Weekly said that “While Vincent Groves cannot be held accountable in a court of law, we hope this long-awaited resolution brings answers and a measure of peace to Rhonda Fisher’s family and friends.”
This case marked the seventh cold case the Douglas County Sheriff’s Office solved in seven years. Further, modern DNA technology and careful preservation of evidence allowed the investigators to overcome time itself. In addition, serial killer private investigators in Oklahoma City and Edmond now use similar DNA strategies in reviewing decades-old evidence. Moreover, Fisher’s case is an example of how forensic science always progresses and works for investigators to serve justice, no matter how long the investigation takes.
Conclusion
Rhonda Marie Fisher’s murder shows how serial killer private investigators remain committed to their work even in the face of overwhelming odds. Modern DNA technology gave 38-year-old evidence its voice and turned it into definitive answers, linking her death with Vincent Darrell Groves and giving her family long-overdue closure. Advanced forensic science, coupled with painstaking evidence preservation and an intensive investigative drive, means that no serial killer can escape accountability indefinitely. Whether investigating an active homicide or a series of cold cases going back decades, professional serial killer private detectives in Oklahoma City, Edmond, and Norman bring cutting-edge forensic analysis in pursuit of justice for the victims.
Contact our serial killer investigation services at (405) 435-8355 Email: makayla@ojpslegal.com
