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Technical Tracks Errors

Examples of Errors in Forensic Science

Analyst/Expert Error

  • Errors due to human bias (i.e., cognitive bias, confirmation bias)
  • Forensic examiner variability
  • Errors due to improperly collected or improperly labeled evidence from crime scenes
  • Errors due to break in the chain of custody
  • Errors due to contamination and mislabeling of evidence
  • Errors due to mishandling (i.e., losing samples, sample mix-ups, sample mislabeling and sample contamination)
  • Errors due to misinterpretation of evidence
  • Errors due to misinterpreting data
  • Errors in poorly following best practices, processes and methods
  • Errors due to poor documentation and transcriptions
  • Errors due to inadequately trained personnel
  • Errors due to analyst incompetence
  • Errors due to failure to review the analysis of the original analyst
  • Errors due to misinterpretation of post-mortem artifacts (i.e., artifacts due to resuscitation, exhumation, decomposition, embalming, rigor mortis, toxicological, environmental)
  • Measurement errors (i.e., systematic, random)


  • Errors due to examiner fraud
  • Errors due to falsified reports
  • Errors due to suppression of exculpatory evidence
  • Errors due to exaggeration of test results
  • Errors due to false testimony about test results

Methods/protocol error

  • Errors due to unvalidated methods
  • Errors due to methods without scientific underpinnings
  • Errors due to inaccurate and misleading statistics
  • Error rates in scientific techniques
  • Measurement errors (i.e., systematic, random)

Instrumentation/Technology Limitations

  • Errors in software packages
  • Error rates in technology solutions
  • Laboratory equipment errors (i.e., poor or no calibrations)
  • Measurement errors (i.e., systematic and random)
  • Errors due to deficiencies in laboratory reference materials



Created February 24, 2015, Updated March 29, 2019