CONGRESS 2023 - The Lundy Murders – the role and reliability of immunohistochemistry in forensic neuropathology practice
Mark Lundy was convicted of killing his wife and daughter in 2002 and again in 2015 after a retrial ordered by the Privy Council. His conviction continues to divide public opinion in New Zealand. A key piece of evidence was the presence of small smears on a shirt which prosecution experts identified as central nervous system tissue relying on immunohistochemistry. The successful challenge to his original conviction was part motivated by arguments challenging the reliability of the latter in forensic practice. This has again come under scrutiny following a 2016 report by the US President’s Council of Advisors on Science and Technology. The PCAST concluded that there were two important deficiencies in ensuring scientific validity of so-called ‘feature-comparison methods’. These are procedures by which an examiner seeks to determine whether an evidentiary sample is or is not associated with a source sample based on similar features. Proponents of Lundy’s innocence argue that the application of immunohistochemistry must be regarded as a subjective feature-comparison method. There was a need for (1) clarity about the scientific standards for the validity and reliability of forensic methods and (2) the need to evaluate specific forensic methods to determine whether they have been scientifically established to be valid and reliable. The report emphasized 2 key elements that are required to meet the scientific criteria of foundation validity; (1) a reproducible and consistent procedure and (2) empirical measurements from multiple independent studies of a method’s false positive rate and sensitivity. It is this author’s position that the manner in which the immunohistochemistry was applied in the Lundy case to identify central nervous system tissue was sufficiently robust in terms of rigor and reproducibility and that to insist otherwise would be tantamount to believing in biological alchemy.
Download as vCalendar (for Microsoft Outlook etc.)
Import event to your Google Calendar
Mark Lundy was convicted of killing his wife and daughter in 2002 and again in 2015 after a retrial ordered by the Privy Council. His conviction continues to divide public opinion in New Zealand. A key piece of evidence was the presence of small smears on a shirt which prosecution experts identified as central nervous system tissue relying on immunohistochemistry.
The successful challenge to his original conviction was part motivated by arguments challenging the reliability of the latter in forensic practice. This has again come under scrutiny following a 2016 report by the US President’s Council of Advisors on Science and Technology. The PCAST concluded that there were two important deficiencies in ensuring scientific validity of so-called ‘feature-comparison methods’. These are procedures by which an examiner seeks to determine whether an evidentiary sample is or is not associated with a source sample based on similar features. Proponents of Lundy’s innocence argue that the application of immunohistochemistry must be regarded as a subjective feature-comparison method.
There was a need for (1) clarity about the scientific standards for the validity and reliability of forensic methods and (2) the need to evaluate specific forensic methods to determine whether they have been scientifically established to be valid and reliable. The report emphasized 2 key elements that are required to meet the scientific criteria of foundation validity; (1) a reproducible and consistent procedure and (2) empirical measurements from multiple independent studies of a method’s false positive rate and sensitivity.
It is this author’s position that the manner in which the immunohistochemistry was applied in the Lundy case to identify central nervous system tissue was sufficiently robust in terms of rigor and reproducibility and that to insist otherwise would be tantamount to believing in biological alchemy.