Criminal Defense Lawyers

Responding to DNA Testing & Lab Fraud Allegations

Responding to DNA Testing & Lab Fraud Allegations

DNA testing has become a powerful tool in the criminal justice system. However, like with any science, errors can occur and some labs have even been found guilty of outright fraud. So what should defense attorneys do when faced with questionable DNA evidence or allegations of lab misconduct? This article reviews some key strategies and considerations.

Verify the Lab’s Credentials

The first thing any defense lawyer should do is thoroughly vet the laboratory and analysts involved. Were accreditation standards followed? Are personnel properly trained and certified? Does the lab have a clean track record or any marks on it’s reputation? Basically, verify that proper protocols were adhered too from start to finish. If uncertainties exist, bring in independent experts to re-examine records and standard operating procedures.

Resubmit Sample for Independent Analysis

Assuming concerns over sloppy procedures or data manipulation aren’t immediately evident, submiting remaining biological samples for outside testing can prove informative. If results come back markedly different, then serious doubts arise over the initial findings. At a minimum it provides defense a second opinion to reference during trial. Keep in mind that sample quality can degrade over time though, making re-testing difficult in some situations.

Probe the Specifics of the Analysis

Delve into the nuts and bolts of how the DNA profile match was derived. How many loci were examined? What statistical models were used to calculate match probabilities and what assumptions went into them? Does the laboratory have acceptible limits on things like false positives or negitives rates? What objective thresholds determine when examiner judgement calls must be used? The goal is to uncover any weak links in the underlying process which could undermine credibility of the end results.

Question the Chain of Custody

Follow the physical trail of the DNA sample every step of the way – from initial collection at the crime scene, transport to the lab, processing and analysis by technicians, storage, and any re-examination by reviewers or secondary labs. Cross reference the written chain of custody documentation with witness testimony to confirm no breaches occured. If unaccounted for handoffs took place, it raises doubts over whether the evidence was compromised.

Get Other Cases Thrown Out

If serious issues with a laboratory are uncovered, dig into their portfolio for any other suspect cases which might need reexamination. Check public records for overturned convictions tied to the lab in question. The goal is to establish a pattern of shoddy practices which extends beyond you’re particular case. The more scientific misconduct you can reveal, the less credibility the facility will have in the eyes of judge and jury.

Leverage Prior Bad Acts

Intense scrutiny should be applied if dealing with a laboratory or analyst who has previously committed breeches of ethics. Were the violations merely administrative oversights? Or were there intentional acts of data falsification committed which call into question integrity of current staff? Bring this track record to light and argue that past fraudulent behavior is prime indicator of ongoing deception.

Dispute Overstated Conclusions

DNA evidence often appears ironclad to juries when presented definitively from the witness stand. But in truth, there are always margins of uncertainty involved. Challenge experts who overstate conclusions, portraying match probabilities as flawless when questions may exist over accuracy of underlying statistical models. Compel them to acknowledge boxes left unchecked which could poke holes in the decisiveness of their assertions.

Criticize Subjectivity

Human analysts must make judgement calls at certain points when interpreting DNA data. Their thresholds for “matching” peaks and peaks, declaring inconclusive results, or deciding what constitutes contamination can vary. And this subjectivity opens the door to conscious or unconscious biases influencing outcomes. Press lab experts to justify why their choices and conclusions are objective rather than discretionary or opinion-based.

Allege Negligence

Playing up sloppy handling procedures, gaps in the chain of custody, missed retesting, sample contamination, clerical errors, unsupported statistics, etc can paint a picture of systemic carelessness. Assert that the laboratory failed in it’s duty to rigorously confirm the accuracy of it’s DNA analyses before releasing results which irrevocably impacted people’s lives. Portray them as negligent rather than nefarious.

Claim Deliberate Deception

If you uncover clear evidence of ethical violations – falsifying test data, hiding exculpatory results, perjury about methodology or credentials – then make deliberate lab fraud central to the defense strategy. Allege that analysts and management conspired in the deception to coverup shoddy practices which would invalidate DNA matches. The revelation of intentional malfeasance rather than honest mistakes makes criminal liability more likely.

So in summary, thoroughly vet the details, personnel, methods, and past track records tied to any DNA testing the prosecution introduces. Resubmit samples for independent analysis when possible. Probe for weak links in interpretation and statistics. Question handling procedures and analyst judgement calls. Dispute any overstated conclusions. And if genuine malpractice is uncovered, press for allegations of negligence, misconduct, or outright fraudulent behavior. The goal is to poke enough holes that reasonable doubt emerges over the definitive nature of presented evidence.

ASCLD Accreditation Standards
Recent Forensic Lab Scandals
DNA Match Probability Controversies
Subjectivity in Forensic Science
Challenging Chain of Custody
Lab Analysts Fired for Falsifying Results
Problems With DNA Match Statistics
Former Chemist Pleads Guilty to Tampering