- 01 Introduction
- 02 Biology of DNA
- 03 Practical Issues Specific to DNA Evidence
- 04 Introduction to the Forensic DNA Laboratory
- 05 Assuring Quality in DNA Testing
- 06 Understanding a Forensic DNA Lab Report
- 07 Statistics and Population Genetics
- 08 Mitochondrial DNA & Y-STR Analysis
- 09 Forensic DNA Databases
- 10 Collection of DNA Evidence from Suspects and Arrestees
- 11 Pretrial DNA Evidence Issues
- 12 Victim Issues
- 13 Trial Presentation
- 14 Postconviction DNA Cases
- 15 Emerging Trends
Principles of Forensic DNA
for Officers of the Court
for Officers of the Court
Module 11 :: Pretrial Issues
Topic 2 :: Expert Testimony in DNA Cases
"Fit"
There must be a need for scientific evidence in the particular case, and the scientific evidence must fit the facts presented. As one court has explained, evidence must "fit" — that is, it must assist the trier of fact:
Admissibility thus depends in part upon "the proffered connection between the scientific research or test result to be presented and the particular disputed factual issues in the case." 19
As a general rule, DNA match evidence will fit in cases in which identity needs to be proven or if another physical fact (such as the occurrence of sexual contact) is in dispute.
