Canada's three forensic laboratories already have PCR technology, and are perfecting it for use in criminal investigations. Forensic laboratories may not be required to follow standard procedures by law - practice can vary, and results may not be reproducible from one laboratory to another. There may not be enough quality control to ensure the best results. Laboratories in Canada follow strict guidelines published by the Technical Working Group on DNA Analysis Methodology and endorsed by the American Society of Crime Laboratory Directors responsible for laboratory accreditation. These guidelines embrace internationally recognized standards for forensic DNA analysis.
Critics question the interpretation of results using current population genetics theory.
These calculations are based on the documented occurrence of certain genetic markers in known racial types. But subgroups within these racial types may not follow the pattern, leading to false conclusions. Tests on many populations suggest three isn't a single genetic profile that would characterize an ethnic subgroup outside of small, isolated ones where inbreeding may be high. Many states in the US now require that convicted criminals give blood for DNA analysis as a matter of course and this information is then permanently stored in a forensic database. Canada seems to be going the same way.