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Transcript

How DNA Caught the Green River Killer

By Heidi Bekkelund

1.

The First Bodies

Title

On August 15, 1982, a man decided to take a trip down south on the Green River, located in Washington. Along his journey, he came across what he thought was a mannequin floating in the water. In attempts to pick up the mannequin, the man fell into the water, and to his horror, discovered the first body of the Green River Killer. Police were notified and a few more bodies were found in the vicinity that day.

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The Task Force

A special team was formed to find the Green River Killer. A task force this size had not been assembled in Seattle since the Ted Bundy case.

2.

The Task Force

A Bad Start

3.

A Bad Start

The investigation got a very poor start. The police were swamped with the massive amounts of evidence and data they were being given in such a short peiod of time. They were so disorganized that much evidence was lost, misplaced, or simply overlooked. The police had to enlist volunteers from the community to help with the ongoing investigation.

Making Connections

4.

Making Connections

The detectives started by finding a relationship, or connection, between the victims. This will allow them to know who the killer is targeting and why. The police found that all the women knew each other and shared a history of prostitution. The police then began searching the area the girls were known to be around and starting interviewing hundreds of prostitutes. Many were reluctant to comply because of their mistrust with the police.

No Progress

5.

No Progress

For months the police continued to investigate potential suspects. One included a man who sexually assulted one of the women interviewed, but no plausable evidence was found against him. 2 other women claimed a man owning a blue and white truck abducted them and attempted to kill them. The man, by the name of Charles Clark, was pulled over and arrested. After a background check was conducted, it was found that Clark owned 2 guns and the women positively identified him as their abductor. Although he admitted to abducting the two women, Clark had a solid alibi for the times of the Green River killings.

The Profile

6.

The Profile

The police gave out this profile of the killer: The Green River Killer is a confident, yet impulsive middle aged man who most likely knew the murder scenes in order to reanact the crimes in his mind. Probably familiar with the area and most likely to have deep religious convictions. He might have an active interest in police work and the investigation of the recent murders. The killer might contact the police in efforts to assist in the ongoing investigation.

Reworking the Force

7.

Reworking the Force

An agent came in and compiled a report after analyzing all the known data that was highly critical of the current investigation. He believed many changes needed to be made in order for the Green River Killer to be caught. The first thing that happened was a complete reorganization of all the evidence and data that had been collected up to that point. Then, similarities and differences between the victims needed to be established. Captain Frank Adamson came into leadership in 1984 and made durastic changes as well. He relocated the headquarters close to where the crimes were occuring. He then divided the force into teams, hoping to facilitate the organization of the vast amounts of information.

Teams

The new teams Adamson created included:

  • 1 team composed of 7 investigators and 1 sergeant team leader was assigned to handle the victims of the Green River Killer
  • 1 team of similar construction was assigned to information pertaining probable suspects
  • 3 detectives assigned to a newly constructed crime analysis section whose duties involved the follow up of leads, analysis of possible trends and methodologies utilized by the killer, as well as other pertinent information relevant to the case
  • 22 police officers assigned to the task forces proactive squad, which developed new strategies to monitor prostitute acitivites and any unusual activities in the area

New Strategy

A new strategy was implemented into the task force that changed investigators focus from the suspects possible guilt to the suspects possible innocence. This allowed investigators to quickly eliminate people under suspicion who had solid alibis and to concentrate on more probable suspects. Suspects that then remained were prioritized according to their threat: Those that were more closely linked to the victims and fit the profile of the killer were put into category A, and those more less closely linked with the crimes were assigned to categories B and C before they were eventually eliminated.

New Profile

Over time, distinct patterns emerged from the killings that allowed investigators to create a more accurate profile. The killer seemed to have several dumping grounds, which led to the conclusion that the killer thought of the women as "human garbage." The task force also determined that the areas where the bodies were found when plotted on a map roughly formed a triangular shape. It was thought that the killer lived somewhere within the triangle.

10 years later

For years, the case went nowhere and moral amongst the officers was at an all time low. However, almost 10 years later the sheriff at the time showed heavy interest in the case and began renewed investigations into the murders. New technology had been developed and the sheriff made a task force including DNA and forensic experts. DNA samples from suspected killers, specifically Gary Ridgeway, were sent to labs and went under new DNA testing methods.

DNA Profiling

DNA profiling

The way the forensic scientists were able to finally prove Gary Ridgeway was the Green River Killer was because they used a new method of DNA analysis called STR and PCR. An STR (short tandem repeat) can be think of as a short part of your DNA that contains a short string of base pairs. An example of an STR would be: AGCATTCAGAGAGAGAGAGAGTCGATAG. PCR (polymerase chain reaction) is a process where scientists separate the STRs from the DNA helix and create multiple copies of it. Forensics do this same process to the suspect’s DNA and then they compare the DNA to one another. If over 13 of the STRs match with one another then scientists are able to conclude that the suspect was the person who committed the crime.

Conclusion

Over 48 women were killed because of the Green River Killer, and it was because of science that he was found and all the victims gained the justice they deserved.

Conclusion

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