On 8 November 2005 three officers; Dan Kucharski of Calumet County and James Lenk and Andrew Colborn of Manitowoc County enter Steven Avery's trailer for a "final thorough search", as instructed by co-lead investigator Tom Fassbender of the DCI.
A "final thorough search" means that unlike previous searches the scene does not have to remain intact and objects can be moved around this time.
The search of the trailer lasted over 2 and a half hours, of which 1 hours was spent in the bedroom. During the bedroom search James Lenk notices a valet Toyota RAV4 car key lying in plain view next to the record cabinet that he and Colborn had just searched. During previous searches the car key wasn't seen at the location it was now lying.
The cops write down in their reports that the key must've been somewhere in or on the record cabinet. Colborn explained he had moved the record cabinet away from the wall to see if there was anything hidden between the record cabinet and its adjacent desk. The record cabinet was further searched through while it was away from the wall. After the search was complete the record cabinet was put back in almost the same place. The officers believe the key fell out when the record cabinet had been moved away.
At trial the defense questioned the discovery of the key. How come it wasn't found before, during any of the previous five or six entries of the trailer when it was just lying there in plain view? How come it fell from the record cabinet in an angle? And why was there only DNA of Steven Avery on the key and none of the victim?
The prosecution explained that the key wasn't found during the seventh search of the trailer, but rather the second search of the trailer. During the previous six entries the bedroom wasn't always visited, and not every entry was a search. For example there was an entry to check the serial number of Steven's computer in his living room. After it was found the officers left.
Steven Avery’s DNA on the car key
After it's discovery the car key was sent to the Wisconsin State Crime Lab and examined by DNA Technical Unit Leader Sherry Culhane. Culhane discovered a DNA profile on the key which turned out to be Steven Avery's. She found no other DNA profile on the key.
At trial, the defense pointed out this fact and raised the question why only one person's DNA can be on the key and it isn't the DNA of the person who supposedly used the key on a regular basis. The State, through their witness forensic scientist John Ertl, explained that it is not unusual when two people handle an object you will find only the DNA of the second handler, effectively saying Steven Avery was the last person to handle the key. Chances increase when the second handler has to object in his possession for a longer period of time.
Several days later Jerry Buting cross-examined Sherry Culhane. Buting tried to claim when multiple people handle an object there should be a mixture of DNA on that object. Culhane disagreed with Buting and said, like Ertl before her, that in her experience you will find the second handler's DNA.
The valet key at trial
- the key wasn’t found until the seventh search of Steven’s trailer.
- the key was found by James Lenk, who the defense also tried to connect to the blood vial and the bullet.
- when it was found, it lay on the floor right next to the record cabinet where anyone could’ve seen it.
- the key didn't contain any DNA of it's owner, Teresa Halbach. It only contained DNA of Steven Avery.
The prosecution claimed that Steven Avery hid the key somewhere in or near the record cabinet after he obtained it from Teresa Halbach and probably used it to hide the RAV4. In response to the defense's claims the prosecution explained:
- The seven searches weren't all searches. Most of them were entries. For example the very first entry was a quick 5 minute sweep to look for any obvious signs of Teresa. Another entry was done to obtain the serial number of Steven’s computer, which was in his living room, rather than his bedroom.
- Lab technicians Sherry Culhane and John Ertl explained that it's not unusual to find only one person’s DNA on an object. Ertl explained that the likeliness of that happening increases when a person has that object in his possession for a longer amount of time. If only one person’s DNA is to be found it will be the last handler’s DNA. Effectively this would mean Steven Avery was the last person to handle the key.
- It was explained that the record cabinet was moved away from the wall, which would explain the location where the key was found.
Timeline of the key
- Monday 31 October 2005
- 14:30 (approx.) The victim arrives at Avery’s driving her RAV4.
- Tuesday 8 November2005
- 7:30 James Lenk finds the key on the carpet floor of Steven Avery's bedroom, next to a record cabinet. It wasn't seen there before.
- Sherry Culhane receives the valet key and finds Steven's DNA on it. She does not find the victim's DNA.
- Monday 31 October 2005
- 19 February 2007
- John Ertl testifies that it's not unusual to find only the final handler's DNA on the key.
- 26 February 2007
- Culhane is challenged by Jerry Buting who insists there should've been a mixture of DNA on the key. Culhane replies "no (...) the last person is going to be the DNA you pick up".
- 19 February 2007