AC Units and DNA
by Douglas Ankney
Australian researchers at Flinders University have employed a promising new technique to collect and record forensic DNA evidence from crime scenes. A new study appearing in Electrophoresis focused on the DNA retrieved from air conditioning (“AC”) units that circulate a room’s air, including different types of filters at alternate periods.
While a crime scene may be wiped clean of fingerprints, Mariya Goray, senior lecturer in forensic science at Flinders and author of the study, said “it is very unlikely that an average offender, even with forensic awareness, could totally prevent their DNA from being released into the environment.
Samples of Environmental DNA (“eDNA”) from AC units in four offices and four houses were collected at different times following cleaning. Samples were also collected from the air. The eDNA collected on the surfaces of AC units tended to be from previous room occupants while eDNA detected in the air represented more recent occupants. Goray said “[w]e now know that eDNA shed from sources, such as skin or saliva, can be detected in the environment, including soil, ice, air and water. We may be able to use this evidence to prove if someone has been in the room, even if they wore gloves or wiped surfaces clean.”
Collection of trace DNA is growing ever more important in criminal investigations. In Australia, for example, 62% of all samples processed by Forensic Science SA were trace or touch DNA. But success rates with this type of evidence remains poor.
Source: forensicmag.com
More from this issue:
- Forensic Genetic Genealogy: Law Enforcement’s Rapid Adoption Outpacing Adoption of Laws and Ethical Guidelines Regulating Its Use, by Matthew Clarke
- HRDC Files Civil Rights Action on Behalf of Wrongly Convicted Florida Man Who Spent 45 Years in Prison, by Sam Rutherford
- California Supreme Court: Defendant Has Due Process Right to Notice of Prosecution’s Election to Seek Enhanced Sentence in Order to Make Key Decisions About Defense, by Douglas Ankney
- University of New Hampshire Designs a Simpler, Cost-Effective Test to Identify Touch DNA, by Jo Ellen Nott
- Kansas Supreme Court Announces Clarification of Framework for Deciding Whether Confession Is Voluntary and Overrules Precedents That Held Reliability of Confession Is Factor to Be Considered, by Douglas Ankney
- Reform-Minded Prosecutors Face Backlash for Prosecuting Bad Cops, by Sam Rutherford
- Decedent’s End-of-Life Condition and Toxicology May Alter Time-of-Death Estimation, by Douglas Ankney
- Fourth Circuit Vacates Where Instructions Failed to Inform Jury That Mens Rea of ‘Knowingly or Intentionally’ Applies to ‘Except as Authorized’ in 21 U.S.C. § 841(a)(1), by Douglas Ankney
- Junk Science Convicted an Innocent Sailor, DNA Exonerated Him Decades Later with the Help of the Innocence Project, by Jo Ellen Nott
- Third Circuit Denies Prosecutor’s Claim of Absolute Immunity Where Wrongfully Convicted Man’s Complaint Alleged Facts Sufficient to Support Finding That Prosecutor’s Actions Served ‘Investigatory Function’, by Douglas Ankney
- New York Court of Appeals: Dismissal Required Where Prosecution Failed to Explain Repeated Requests for Post-Readiness Adjournment, by Sam Rutherford
- Delaware Supreme Court: Warrant That Authorized Search of ‘Any and All’ Data of Named Files on Cellphone Is Invalid General Warrant That Also Failed to Include Temporal Limitation, by Douglas Ankney
- Colorado Supreme Court Announces Parole Board Not Statutorily Required to Consider ‘Demonstrated Maturity and Rehabilitation’ When Deciding Whether to Release Sex Offenders Who Received Adult Sentences for Crimes Committed as Juveniles, by Sam Rutherford
- Massachusetts Supreme Judicial Court Affirms Trial Court’s Exclusion of Expert Testimony on iPhone’s Frequent Location History Data as Not Sufficiently Reliable Under Daubert-Lanigan Standard, by Douglas Ankney
- DOJ Creates Database to Track Federal Law Enforcement Officers Accused of Misconduct, by Sam Rutherford
- Misuse of Facial Recognition Technology Threatens Everyone, by Michael Thompson
- Idaho Supreme Court Admitting Video of Child-Witness Interviews at Trial Violates Confrontation Clause, by Sam Rutherford
- Bluetooth Surveillance Tool Added to List of Known Cache of DHS’ Surveillance Technology, by Douglas Ankney
- California Court of Appeal: Statistical Evidence Showing Racial Disparity Combined With Evidence Showing Non-Minority Defendants Charged With Lesser Crimes Establishes Prima Facie Case Under California Racial Justice Act, by Douglas Ankney
- AC Units and DNA, by Douglas Ankney
- Indiana Supreme Court Clarifies Framework for Determining When Courts May Apply Cash Bail to Public-Defender Costs and to Fines, Costs, and Fees, by Douglas Ankney
- Changes to Appeals of Pretrial Detention Decisions Prompts Illinois Supreme Court to Adopt Changes to Appellate Rules, by Douglas Ankney
- First Circuit: Defendant Did Not Understand Consequences of Guilty Plea Because District Court and Counsel Led Him to Reasonably Believed Plea Agreement Would Result in Sentence Below Applicable Mandatory Minimum, by David Reutter
- U.S. Sentencing Commission Votes Unanimously to Restrict Use of Acquitted Conduct at Sentencing, by Sam Rutherford
- Report Finds Inaccurate Field Drug Tests Major Cause of Wrongful Convictions, by Matthew Clarke
- New Research on Predictive Models for Pediatric Head Injuries, by Jo Ellen Nott
- Government Accountability Office Issues a Report on DOJ and DHS Use of Facial Recognition Technology, by Michael Thompson
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- Landmark Drug Possession Reform Based on Unproven Allegations Reversed in Oregon, by Jo Ellen Nott
- Push Notifications Pull to the Forefront, by Michael Thompson
- Second Chances: California Clears Criminal Records, Including Violent Crimes, by Jo Ellen Nott
- New York Court of Appeals Overturns Harvey Weinstein’s Convictions Based on Trial Court Rulings That Admitted Prejudicial ‘Prior Bad Acts’ Into Evidence and Violated His Right to Testify in His Own Defense, by Richard Resch
- News in Brief
More from Douglas Ankney:
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- Eighth Circuit Revives § 1983 Complaint Alleging Jail Detainees’ Death from Stroke was Due to Deliberate Indifference and Failure to Train, July 1, 2026
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- SCOTUS Holds Federal Habeas Court May Not Consider Post-Trial DNA Evidence That Was Never Presented to Jury When Assessing Whether False Informant Testimony Influenced Verdict, July 1, 2026
- Supreme Court of Appeals of West Virginia Announces Six-Factor Test for Evaluating Presentence Motions to Withdraw Guilty Pleas Under Rule 32(e), Holds Binding Plea Agreement Does Not Extinguish Defendant’s Ability to Seek Withdrawal, July 1, 2026
- New Jersey Lawmakers Pass “Female Incarcerated Person’s Rights Protection Act”, July 1, 2026
- Louisiana’s Atavistic Approach to Criminal Sentencing and Parole Demonstrates Politicians’ Failure to Learn from Past Mistakes, July 1, 2026
- California Supreme Court Announces Amended § 1170(b) Applies Retroactively to Plea-Bargained Upper Term Sentences, July 1, 2026
- Michigan Supreme Court Announces Betts Decision Invalidating 2011 SORA as Ex Post Facto Punishment Applies Retroactively to Defendants on Collateral Review, July 1, 2026
- South Carolina Supreme Court Announces Formal Adoption of Fourth Circuit’s Three-Step Cheek Framework for Evaluating Improper Third-Party Contacts With Jurors Under Remmer, Reverses Murdaugh Murder Convictions, and Overrules Ethier Regarding Juror Testim, July 1, 2026
More from these topics:
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- Florida Supreme Court Announces “Results” of Postconviction DNA Testing Under § 925.11 Include Underlying Testing Data Necessary for Expert Analysis, Holding That No Additional Burden Applies Once a Motion for Testing Has Been Granted, June 1, 2026. DNA Testing/Samples, Disclosure of Records, Public Records, Forensic Sciences, Scientific Testimony or Evidence.
- Your DNA Was at the Scene, But You Weren’t: How Touch DNA Is Convicting the Innocent, June 1, 2026. DNA Testing/Samples, junk science, Wrongful Conviction, DNA Evidence, Evidence - Admissibility, Claim of Innocence.
- Murder Convictions Tossed for Three Pennsylvania Prisoners After 28 Years, June 1, 2026. Wrongful Conviction, witness misidentification, Forensic Sciences, Evidence - Integrity/Reliability of, Expert and Opinion Testimony.
- Colorado Limits the Use of Faulty Field Drug Tests, May 1, 2026. Forensic Sciences, Drugs - Determination of, Evidence - Integrity/Reliability of, Drug Laws/Offenses, Knowingly and Voluntarily Made.
- No Blood, No Proof: Study Challenges Post-Cleanup DNA Evidence, April 1, 2026. Forensic Sciences, Evidence - Integrity/Reliability of, Daubert Standards, Expert and Opinion Testimony, Scientific Testimony or Evidence.
- New Study Exposes Reliability Gap in Traditional Time-of-Death Methods, April 1, 2026. Forensic Sciences, Evidence - Integrity/Reliability of, Daubert Standards, Expert and Opinion Testimony, Scientific Testimony or Evidence.
- Swabbed at Booking, Searched for Life: How Pre-Conviction DNA Collection Built a Genetic Mass Surveillance System, April 1, 2026. DNA Testing/Samples, Databases, Effects of Mass Incarceration.
- The Unintentional Informant: Household Pets as Vectors of Human DNA, March 1, 2026. DNA Testing/Samples, Forensic Sciences, DNA Evidence, Evidence - Integrity/Reliability of, Scientific Testimony or Evidence.
