Expert witnessWisconsin State Crime Laboratory (Madison)

Sherry Culhane

Wisconsin Crime Lab DNA analyst who examined evidence from the RAV4, a key, and a bullet fragment.

1,958 lines·35 proceedings·24 mentions·2 trials

About

Sherry Culhane, a Wisconsin Crime Lab DNA analyst, testified about testing evidence in the Avery and Dassey prosecutions. She reported profiles from the RAV4, a key, a hood latch, and a bullet fragment that she attributed to Steven Avery or Teresa Halbach, while describing the charred-tissue profile as too limited to identify Halbach as its source under laboratory policy. In Avery’s trial, she acknowledged that her DNA appeared in a negative control during bullet-fragment testing, that the control ordinarily called for an inconclusive result, and that she used an approved deviation to report her conclusion. She maintained that the contamination was confined to the control, not the evidence sample, but could not say with complete certainty how it occurred. In Dassey’s trial, she said no evidence profile she developed was consistent with him; she also explained that undetected DNA, limited testing, and untested items could not establish whether someone had been at a scene.

Trial Record (35)

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

In Steven Avery's 2007 trial, State DNA analyst Sherry Culhane testified about profiles from the RAV4 and other evidence. Her bullet-fragment conclusion drew sustained questioning because her DNA appeared in a negative control and she used a deviation to report the result.

Day 1

Feb 12, 2007

OpeningState’s Opening StatementKenneth R. KratzMentioned

Summary

Kratz previewed the State's theory of Halbach's death and the vehicle, DNA, remains, firearm, and witness evidence it expected to present.

Mentioned in this proceeding.

Day 10

Feb 23, 2007

CrossRonald L. Groffy — CrossRonald L. GroffyJerome F. ButingMentioned

Summary

Groffy described limits on his RAV4 testing, clarified photograph timing and fingerprint markings, and testified about the driver's-seat fit. The court admitted the vehicle photographs.

Mentioned in this proceeding.

DirectSherry Culhane — DirectSherry CulhaneNorman A. Gahn468lines spoken

Summary

Culhane presented DNA comparisons from the RAV4, charred remains, bullet fragment, hood latch, and key, and disclosed contamination in a bullet-test negative control.

ProceduralEnd-of-day jury admonition after Culhane’s direct examinationMentioned1line spoken

Summary

The court gave jurors weekend instructions, then admitted forensic exhibits and reviewed outstanding exhibit status. The defense reserved its position on whether five Crime Lab reports should go to the jury during deliberations.

Mentioned in this proceeding.

Day 11

Feb 26, 2007

CrossSherry Culhane — CrossSherry CulhaneJerome F. Buting851lines spoken

Summary

Buting challenged the limits of Culhane's DNA conclusions and her bullet-fragment result, focusing on a contaminated control, a protocol deviation, and its omission from her final report.

RedirectSherry Culhane — RedirectSherry CulhaneNorman A. Gahn67lines spoken

Summary

Culhane defended her bullet DNA conclusion despite contamination in the test control, explained her protocol deviation, and identified a buccal-swab envelope that the court kept closed pending recross.

ProceduralBuccal-swab envelope hearing: chain of custody and planting-theory disputeMentioned

Summary

Counsel disputed the buccal-swab envelope's seal and the scope of the defense's planting theory; the judge set a procedure for showing and describing the envelope before opening it.

Mentioned in this proceeding.

RedirectSherry Culhane — Redirect ContinuedSherry CulhaneNorman A. Gahn32lines spoken

Summary

Culhane described the opened package's swab kit and testified that the inner envelope's seals appeared unbroken, while saying its markings did not show when she resealed it.

RecrossSherry Culhane — RecrossSherry CulhaneJerome F. Buting44lines spoken

Summary

Culhane agreed that without a protocol-permitted deviation, the bullet DNA result would have been reported as inconclusive; she maintained that her DNA contaminated the control, not the evidence extract.

RedirectSherry Culhane — Further RedirectSherry CulhaneNorman A. Gahn3lines spoken

Summary

Culhane defended the bullet-test protocol deviation, saying her DNA was in the control, not the evidence sample.

RecrossSherry Culhane — Further RecrossSherry CulhaneJerome F. Buting7lines spoken

Summary

Culhane said the DNA in the bullet-test control was hers but could not say with complete certainty how the control became contaminated.

Day 12

Feb 27, 2007

ProceduralRenewed Motion to Suppress Bullet Fragment FL Test ResultsMentioned

Summary

The defense renewed its motion to suppress the bullet fragment FL test results; the court took it under advisement and allowed the State time to respond.

Mentioned in this proceeding.

Day 16

Mar 5, 2007

DirectMarc LeBeau — DirectMarc LeBeauNorman A. GahnMentioned

Summary

Marc LeBeau testified that FBI testing found EDTA in Steven Avery's purple-topped blood tube but not in three bloodstain swabs from Teresa Halbach's RAV4. He opined that the tested stains did not come from that tube.

Mentioned in this proceeding.

Day 17

Mar 6, 2007

ProceduralDefense motion to preserve blood evidenceMentioned

Summary

The court invited a proposed order preserving RAV4 blood evidence and a blood vial, while leaving preservation details for later.

Mentioned in this proceeding.

DirectMarc LeBeau — DirectMarc LeBeauNorman A. GahnMentioned

Summary

LeBeau testified that EDTA was detected in the submitted blood tube but not in tested RAV4 swabs, and opined that the stains could not have come from that tube. The court rejected a broader planting question.

Mentioned in this proceeding.

Day 18

Mar 7, 2007

DirectMark Wiegert — DirectMark WiegertKenneth R. KratzMentioned

Summary

Wiegert described the blood-vial inquiry and FBI transfer; the court limited secondhand testimony and barred an access question.

Mentioned in this proceeding.

Day 19

Mar 8, 2007

ProceduralMotion for judgment of acquittalMentioned

Summary

The defense sought acquittal on four counts, concentrating on whether the evidence supported false imprisonment. The State opposed the motion; the court did not rule.

Mentioned in this proceeding.

ProceduralRenewed fair-forensic-testing motionMentioned

Summary

The defense sought suppression of Item FL bullet DNA evidence or a jury instruction; the State opposed, and the court reserved its ruling.

Mentioned in this proceeding.

Day 21

Mar 12, 2007

ProceduralRulings on fair testing, search suppression, and charge dismissalMentioned

Summary

The court denied renewed fair-testing and search-suppression motions, but dismissed the false-imprisonment charge for insufficient evidence.

Mentioned in this proceeding.

Day 23

Mar 14, 2007

ClosingState’s Closing Argument by Kenneth KratzKenneth R. KratzMentioned

Summary

Kratz began the State's closing with the RAV4, blood and DNA evidence, and burned electronics; an objection led the court to remind jurors that argument is not fact.

Mentioned in this proceeding.

ClosingState’s Closing Argument ResumesKenneth R. KratzMentioned

Summary

Kratz completed the State's closing by linking its timeline, burn-area, firearm, and DNA arguments and requesting guilty verdicts on the three remaining charges.

Mentioned in this proceeding.

ClosingDefense Closing Argument ResumesJerome F. ButingMentioned

Summary

Buting challenges the key, RAV4 blood, bullet DNA, and EDTA evidence as he argues the investigation left reasonable doubt; a third-party-liability objection interrupts his closing.

Mentioned in this proceeding.

Day 24

Mar 15, 2007

ClosingDefense closing argument by Dean StrangDean A. StrangMentioned

Summary

Strang urged jurors to find reasonable doubt, challenging the State's timeline, investigative conduct, forensic testing, and interpretation of physical evidence.

Mentioned in this proceeding.

RebuttalState rebuttal closing argument by Kenneth KratzKenneth R. KratzMentioned

Summary

Kratz rebutted the defense's planting theory and forensic challenges; after a defense objection, the court reminded jurors that arguments are not evidence.

Mentioned in this proceeding.

Day 26

Mar 17, 2007

Jury QuestionsJury request and rereading of Culhane’s rifle DNA testimonySherry CulhaneMentioned

Summary

The jury heard a readback of Culhane's negative DNA findings for the tested rifle barrel and trigger area, including the limit of her swabbing.

Mentioned in this proceeding.

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

Sherry Culhane testified as a DNA analyst in Brendan Dassey's 2007 trial, attributing DNA from RAV4 evidence and a garage bullet fragment to Steven Avery or Teresa Halbach. She said no evidence profile she developed was consistent with Dassey, while explaining that absent DNA and untested items did not establish his absence from a scene.

Day 1

Apr 16, 2007

OpeningState's Opening StatementKenneth R. KratzMentioned

Summary

Kratz outlined the State's theory that Dassey helped Avery assault and kill Halbach, then previewed Dassey's recorded statement and evidence the State said would corroborate it.

Mentioned in this proceeding.

Day 3

Apr 18, 2007

DirectSherry Culhane — DirectSherry CulhaneNorman A. Gahn1highlight238lines spoken

Summary

DNA analyst Sherry Culhane attributed DNA from several RAV4 items and a key to Steven Avery, and DNA from the cargo area, a Pepsi can, and a bullet fragment to Teresa Halbach; she limited her conclusion about charred tissue to a partial-profile comparison.

Highlights (1)

testimony highlightCulhane testified that DNA profiles from the identified RAV4 passenger-compartment samples were consistent with Steven Avery's reference profile and gave her opinion that he was the source.Open in transcript →

CrossSherry Culhane — CrossSherry CulhaneMark R. Fremgen1highlight166lines spoken

Summary

Culhane said none of the evidence samples from which she developed a DNA profile was consistent with Brendan Dassey, while explaining that some items received blood testing but no further DNA analysis.

Highlights (1)

testimony highlightCulhane said blood testing at the end of the firearm's barrel was negative and she developed no DNA profile from the firearm.Open in transcript →

RedirectSherry Culhane — RedirectSherry CulhaneNorman A. Gahn1highlight48lines spoken

Summary

Culhane explained limits of DNA testing, confirmed she found no blood on Brendan Dassey's jeans, and said absent detectable DNA does not establish whether someone was at a crime scene.

Highlights (1)

testimony highlightCulhane estimated about 350 laboratory submissions in the case, about 180 to the DNA unit, and said she could not say whether the DNA-unit total was a unit record.Open in transcript →

RecrossSherry Culhane — RecrossSherry CulhaneMark R. Fremgen2highlights32lines spoken

Summary

Culhane explained her DNA-testing choices and confirmed that shell casings, other areas of the jeans, and bedding had not received the testing defense counsel asked about.

Highlights (2)

testimony highlightCulhane could not recall the extent of apparent bleach staining on the jeans. She said one small brownish stain tested negative and no other areas were swabbed.Open in transcript →

testimony highlightCulhane agreed bedding can be useful to test in a sexual-assault investigation but said none had been submitted to her and she had not tested any.Open in transcript →

DirectNick Stahlke — DirectNick StahlkeNorman A. GahnMentioned

Summary

Nick Stahlke interpreted RAV4 bloodstains as consistent with an actively bleeding person in the passenger area and a possible loading of a body with bloody head hair into the cargo area.

Mentioned in this proceeding.

Day 7

Apr 23, 2007

CrossMichael Riddle — CrossMichael RiddleNorman A. GahnMentioned

Summary

Riddle explained why shell casings may yield no comparable prints and agreed that finding no Steven Avery fingerprints in the RAV4 did not establish his absence.

Mentioned in this proceeding.

Day 9

Apr 25, 2007

ClosingProsecution closing argument by Thomas J. FallonThomas J. FallonMentioned

Summary

Fallon argued that Dassey's statements were corroborated, that his alleged acts made him a party to all three crimes, and that the jury should return guilty verdicts.

Mentioned in this proceeding.

ClosingDefense closing argument by Mark R. FremgenMark R. FremgenMentioned

Summary

Fremgen argued that forensic gaps and changing details in Dassey's statements left reasonable doubt.

Mentioned in this proceeding.

RebuttalProsecution rebuttal closing argument by Thomas J. FallonThomas J. FallonMentioned

Summary

Fallon rebutted challenges to Dassey's statements and the forensic gaps, played part of the March 1 interview, and requested guilty verdicts.

Mentioned in this proceeding.