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Steven Avery & Brendan Dassey— Case Archive
personpersonThomas FassbenderThomas FassbenderSpecial agent involved in Avery-property searches and interviews of Brendan Dassey.← All People
Law enforcementWisconsin Department of Justice, Division of Criminal Investigation

Thomas Fassbender

Special agent involved in Avery-property searches and interviews of Brendan Dassey.

AppearedSteven AveryBrendan Dassey
1,026 lines·71 proceedings·63 mentions·2 trials

About

Special Agent Thomas Fassbender testified about coordinating searches of the Avery property with Mark Wiegert and handling Teresa Halbach’s RAV4. He described searches that became more detailed as investigators obtained information and addressed the later discovery of a Toyota key, license plates, and bone pieces, while distinguishing his own observations from others’ findings. In Avery’s trial, defense questioning challenged repeated entries into the trailer and garage, search records, and his assignment of Manitowoc officers; Fassbender acknowledged the appearance-of-conflict concern behind Calumet County’s lead role. In Dassey’s trial, he also recounted Dassey’s reported account of cleaning the garage floor. On cross-examination, Fassbender acknowledged that he first suggested blood during that interview and corrected testimony about the source of leg irons.

Trial Record (71)

AverySteven AveryFeb 12, 2007 – Mar 18, 2007Called by prosecution

Special Agent Thomas Fassbender testified in Steven Avery's 2007 trial about directing property searches with Mark Wiegert and the handling of Teresa Halbach's RAV4. Defense questioning tested repeated searches, scene records, and his assignment of Manitowoc officers.

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DirectThomas Fassbender — DirectThomas FassbenderKenneth R. Kratz6highlights243lines spoken

Summary

Fassbender outlined the November 5–12 searches, RAV4 handling, and discoveries of a Toyota key, license plates, and bone pieces; a discovery dispute was also raised.

Highlights (6)

testimony highlightFassbender identifies himself and Mark Wiegert as the two lead investigators and describes briefings and group decisions that directed the investigation.Open in transcript →
testimony highlightFassbender explains that the initial building sweeps sought Teresa alive and checked safety before more detailed searches began.Open in transcript →
testimony highlightFassbender limits his account of continuous RAV4 guarding to when he reached the crusher area, then describes its removal by a wrecker and loading into an enclosed trailer.Open in transcript →
evidence eventDuring a more thorough search of Steven Avery's trailer, evidence technicians show Fassbender a Toyota key with a blue fob; he directs that it be preserved and taken to the Crime Lab.Open in transcript →
Show all 6 highlights
evidence eventFassbender says searchers found two license plates in a salvaged vehicle and identified them as Teresa's.Open in transcript →
evidence eventFassbender describes pieces of bone found in a burn area behind the garage next to Steven Avery's residence and says the Crime Lab was asked to help process the area.Open in transcript →
CrossThomas Fassbender — CrossThomas FassbenderJerome F. Buting4highlights369lines spoken

Summary

Buting challenged Fassbender on search-team choices, repeated searches, scene logs, and an anonymous smelter lead; Fassbender acknowledged limits in the trailer and garage evidence.

Highlights (4)

impeachmentUsing Exhibit 142, Buting established that the log recorded Lieutenant Lenk signing out on November 5 but showed no sign-in for him on that log. Fassbender said Lenk might have used another route or arrived before the log began; he did not recall seeing Lenk arrive.Open in transcript →
confrontationFassbender said he did not know on November 5 that Lenk and Colborn had been deposed in Avery's civil case. Asked whether that knowledge would have changed their search assignment, he said he still would have used them, while emphasizing his need for trained evidence technicians.Open in transcript →
testimony highlightFassbender agreed that the Toyota key was found during the seventh entry into Avery's trailer, after six earlier entries, and confirmed he was not present when it was discovered.Open in transcript →
testimony highlightQuestioned about an anonymous letter referring to the property's aluminum smelter, Fassbender said he believed it was sent for print analysis only after Buting pointed it out. He said arson investigators had examined the smelter and thought it did not appear to have been used for a while.Open in transcript →

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DasseyBrendan DasseyApr 16, 2007 – Apr 25, 2007Called by prosecution

Thomas Fassbender testified for the prosecution in Brendan Dassey's 2007 trial about the Avery property search, the RAV4, and Dassey's reported garage-floor cleanup account. On cross-examination, he acknowledged that he first suggested blood during the garage-floor interview.

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DirectThomas Fassbender — DirectThomas FassbenderKenneth R. Kratz4highlights199lines spoken

Summary

Fassbender described the Avery Yard search, RAV4 handling, recovered items, and Dassey's reported February 27 account of garage-floor cleanup; the court limited two exhibit admissions.

Highlights (4)

testimony highlightFassbender identified photographs of the RAV4 and described branches, posts, plywood, auto parts, and a vehicle hood around it, which he regarded as an attempt to conceal it.Open in transcript →
testimony highlightFassbender said that, in his observation, Brutus alerted on the RAV4. He clarified that the secured vehicle remained at the scene for about two more hours before removal.Open in transcript →
Quote“Brutus clearly, at least to my observations, alerted on that -- that vehicle.”— Thomas FassbenderFassbender stated his own observation of the search dog's response while expressly qualifying it as his observation.Open in transcript →
testimony highlightDescribing the February 27 interview, Fassbender said Dassey initially described garage-floor stains as dark red but believed them to be oil, then said he believed the substance could have been blood. Fassbender said that account was one reason for a later interview, not the only reason.Open in transcript →
CrossThomas Fassbender — CrossThomas FassbenderRaymond L. Edelstein3highlights150lines spoken

Summary

Edelstein challenged the physical links to Dassey and elicited Fassbender's acknowledgment that he first suggested blood in the garage-floor interview.

Highlights (3)

impeachmentFassbender corrected his direct testimony about the leg irons: Exhibits 61 and 62 came from Ms. Tadych's bedroom, and his earlier identification of one set as coming from Steven Avery's house was an error. He cautioned that he would need lab reports to confirm whether these exhibits had been processed.Open in transcript →
Quote“Correct. With the caution that I'm not positive they were processed. I'd have to look at the Crime Lab reports to make sure.”— Thomas FassbenderHe qualified his answer about the absence of DNA connecting the leg irons to Dassey.Open in transcript →
admissionFassbender agreed that he, rather than Dassey, first suggested blood during their discussion of the garage-floor stain. He said Dassey later stated he believed it was blood, after Fassbender's question.Open in transcript →
RedirectThomas Fassbender — RedirectThomas FassbenderKenneth R. Kratz2highlights5lines spoken

Summary

Fassbender identified two tagged pairs of handcuffs from Barb Janda's bedroom and confirmed restraints were also found in Steven Avery's bedroom.

Highlights (2)

testimony highlightAfter reviewing evidence bags, Fassbender identified Tags 8266 and 8267 as each containing a pair of silver handcuffs from Barb Janda's bedroom.Open in transcript →
testimony highlightFassbender agreed that handcuffs and leg irons were also recovered from Steven Avery's bedroom.Open in transcript →

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DirectRobert H. Gordon — DirectRobert H. GordonMark R. FremgenMentioned

Summary

Robert H. Gordon testified that his testing and review of interview materials led him to conclude Brendan Dassey was highly suggestible when questioned with leading questions or mild pressure. The examination also addressed disputed IQ-chart labeling and records Gordon reviewed after writing his report.

Mentioned in this proceeding.

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