Läkaren under luppen: En granskning av rättsmedicinsk expertbevisning i brottmål
(2022) JURM02 20221Department of Law
Faculty of Law
- Abstract
- Expert witnesses are an increasingly more common phenomena in the Swedish trial. Forensic physicians, forensic scientists and other experts give their opinions on complex matters in the hope that it will help the fact-finder understand certain circumstances. It is a difficult task and a lot can go wrong along the way.
The purpose of this investigation is to improve the quality of certain aspects of forensic medical evidence. The investigation analyses three main components of forensic medicine in the swedish criminal trial: the probability scale used to communicate the meaning of a forensic report or a postmortem examination, the probability scale used to communicate the meaning of a medical age assessment and certain foundational... (More) - Expert witnesses are an increasingly more common phenomena in the Swedish trial. Forensic physicians, forensic scientists and other experts give their opinions on complex matters in the hope that it will help the fact-finder understand certain circumstances. It is a difficult task and a lot can go wrong along the way.
The purpose of this investigation is to improve the quality of certain aspects of forensic medical evidence. The investigation analyses three main components of forensic medicine in the swedish criminal trial: the probability scale used to communicate the meaning of a forensic report or a postmortem examination, the probability scale used to communicate the meaning of a medical age assessment and certain foundational aspects of forensic medical science in general.
Through the use of a probability based method for the evaluation of evidence, sources of error are identified in the material. The sources of error are then analysed in the light of two requirements that can be applied to expert witnesses in general: the requirement of aboveboard information and the requirement of aboveboard communication. The requirements are identified through a conceptualisation of the expert witness' role in the trial.
The results of the investigation show that all three analysed aspects of forensic medicine contain sources of error. The probability scales comment on things they should not comment on and the medical age assessments are based on scientifically poor studies. Furthermore, certain foundational aspects of forensic medical science are probabilistically problematic. These sources of error entail that the three analysed aspects of forensic medicine meet neither the requirement of aboveboard information nor the requirement of aboveboard communication.
In conclusion, I suggest how the probability scales can be redesigned to better meet the requirements. For example, it can be made clear that the forensic physician is only supposed to evaluate and communicate the likelihood-ratio of a piece of evidence and nothing else. Other suggestions include that the National Board of Forensic Medicine should develop a method for defining alternative hypotheses and that the medical age assessments should be based on studies with more relevantly delimited populations. (Less) - Abstract (Swedish)
- Expertutlåtanden som bevismedel har blivit ett allt vanligare fenomen i den svenska rättegången. Rättsläkare, forensiker och andra experter uttalar sig om komplexa förhållanden i hopp om att upplysa domare om vilken betydelse en omständighet har. Det är inte alltid en lätt uppgift och mycket kan gå fel på vägen.
Syftet med denna undersökning är att kvalitetssäkra vissa aspekter av den rättsmedicinska expertbevisningen. Undersökningen analyserar tre stycken huvudkomponenter av den rättsmedicinska bevisföringen i straffprocessen: den sannolikhetsskala som används för att kommunicera betydelsen av ett rättsintyg eller en obduktion, den sannolikhetsskala som används för att kommunicera betydelsen av en rättsmedicinsk åldersbedömning och... (More) - Expertutlåtanden som bevismedel har blivit ett allt vanligare fenomen i den svenska rättegången. Rättsläkare, forensiker och andra experter uttalar sig om komplexa förhållanden i hopp om att upplysa domare om vilken betydelse en omständighet har. Det är inte alltid en lätt uppgift och mycket kan gå fel på vägen.
Syftet med denna undersökning är att kvalitetssäkra vissa aspekter av den rättsmedicinska expertbevisningen. Undersökningen analyserar tre stycken huvudkomponenter av den rättsmedicinska bevisföringen i straffprocessen: den sannolikhetsskala som används för att kommunicera betydelsen av ett rättsintyg eller en obduktion, den sannolikhetsskala som används för att kommunicera betydelsen av en rättsmedicinsk åldersbedömning och vissa rättsmedicinska vetenskapliga utgångspunkter i allmänhet.
Med hjälp av beviskraftmetoden - en sannolikhetsorienterad bevisvärderingsmetod - identifieras olika felkällor i granskningsmaterialet. Felkällorna granskas sedan i ljuset av två stycken krav som man i allmänhet kan ställa på expertbevisning: kravet på rättvisande information och kravet på rättvisande kommunikation. Kraven identifieras genom en konceptualisering av expertens funktionella roll i rättegången.
Resultatet av undersökningen visar att samtliga tre aspekter av den rättsmedicinska bevisningen innehåller felkällor. Sannolikhetsskalorna uttalar sig om saker som de inte borde uttala sig om och de rättsmedicinska åldersbedömningarna baseras på vetenskapligt bristfälliga studier. Även vissa rättsmedicinska vetenskapliga utgångspunkter är sannolikhetsteoretiskt problematiska. Felkällorna medför att de tre aspekterna av den rättsmedicinska bevisningen inte kan anses leva upp till vare sig informationskravet eller kommunikationskravet.
Avslutningsvis ges förslag på hur sannolikhetsskalorna kan omformuleras för att bättre leva upp till kraven. Till exempel kan det tydliggöras att läkaren endast ska uttala sig om beviskraften hos ett bevisfaktum. Andra förslag på förbättringar är att det bör utvecklas en metod för hur alternativhypoteser definieras och att de rättsmedicinska åldersbedömningarna bör baseras på studier med bättre avgränsade referensklasser. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9079888
- author
- Thellner, Alexander LU
- supervisor
- organization
- alternative title
- The forensic physician under scrutiny: An examination of forensic medical evidence in the Swedish criminal trial
- course
- JURM02 20221
- year
- 2022
- type
- H3 - Professional qualifications (4 Years - )
- subject
- keywords
- allmän rättslära, jurisprudence, rättsmedicin, expertbevisning
- language
- Swedish
- id
- 9079888
- date added to LUP
- 2022-06-09 12:31:38
- date last changed
- 2022-06-09 12:31:38
@misc{9079888,
abstract = {{Expert witnesses are an increasingly more common phenomena in the Swedish trial. Forensic physicians, forensic scientists and other experts give their opinions on complex matters in the hope that it will help the fact-finder understand certain circumstances. It is a difficult task and a lot can go wrong along the way.
The purpose of this investigation is to improve the quality of certain aspects of forensic medical evidence. The investigation analyses three main components of forensic medicine in the swedish criminal trial: the probability scale used to communicate the meaning of a forensic report or a postmortem examination, the probability scale used to communicate the meaning of a medical age assessment and certain foundational aspects of forensic medical science in general.
Through the use of a probability based method for the evaluation of evidence, sources of error are identified in the material. The sources of error are then analysed in the light of two requirements that can be applied to expert witnesses in general: the requirement of aboveboard information and the requirement of aboveboard communication. The requirements are identified through a conceptualisation of the expert witness' role in the trial.
The results of the investigation show that all three analysed aspects of forensic medicine contain sources of error. The probability scales comment on things they should not comment on and the medical age assessments are based on scientifically poor studies. Furthermore, certain foundational aspects of forensic medical science are probabilistically problematic. These sources of error entail that the three analysed aspects of forensic medicine meet neither the requirement of aboveboard information nor the requirement of aboveboard communication.
In conclusion, I suggest how the probability scales can be redesigned to better meet the requirements. For example, it can be made clear that the forensic physician is only supposed to evaluate and communicate the likelihood-ratio of a piece of evidence and nothing else. Other suggestions include that the National Board of Forensic Medicine should develop a method for defining alternative hypotheses and that the medical age assessments should be based on studies with more relevantly delimited populations.}},
author = {{Thellner, Alexander}},
language = {{swe}},
note = {{Student Paper}},
title = {{Läkaren under luppen: En granskning av rättsmedicinsk expertbevisning i brottmål}},
year = {{2022}},
}