National DNA database
DNA technology has proved to be a valuable investigative tool which has helped to exonerate the innocent and to bring those responsible for serious crimes to justice. The legislation that Parliament enacted to govern the use of this technology within the criminal justice system has been found by Canadian courts to be respectful of the constitutional and privacy rights of suspects, and of persons found guilty of designated offences.
On December 11, 1999, The Canadian Government agreed upon the DNA Identification Act. This would allow a Canadian DNA data bank to be created and amended for the criminal code. This provides a mechanism for judges to request the offender to provide blood, buccal swabs, or hair samples from DNA profiles. This legislation became official on June 29, 2000. Canadian police has been using forensic DNA evidence for over a decade. It has become one of the most powerful tools available to law enforcement agencies for the administration of justice.
DNA is highly discriminatory, which can make it a powerful tool in identifying individuals. Each person’s DNA is unique to them to the slight exception of identical (monozygotic and monospermotic) twins, who start out from the identical genetic line of DNA but during the twinning event have incredibly small mutations which can be detected now (for all intents and purposes, compared to all other humans and even to theoretical "clones, [who would not share the same uterus nor experience the same mutations pre-twinning event]" identical twins have more identical DNA than is probably possible to achieve between any other two humans). Tiny differences between identical twins can now (2014) be detected by next generation sequencing. See: Weber-Lehman et al. 2014. Finding the needle in the haystack: Differentiating "identical" twins in paternity testing and forensics by ultra-deep next generation sequencing. Forensic Science International: Genetics; 9: 42-46. For current fiscally available testing, "identical" twins cannot be easily differentiated by the most common DNA testing, but it has been shown to be possible. While other siblings (including fraternal twins) share about 50% of their DNA, monozygotic twins share virtually 99.99%. Beyond these more recently discovered twinning-event mutation disparities, since 2008 it has been known that people who are identical twins also each have their own set of copy number variants, which can be thought of as the number of copies they each personally exhibit for certain sections of DNA 
DNA can be extracted from small biological samples, such as a few drops of blood, using modern technology. The sample can be analyzed, which creates a DNA profile that is used to identify the suspect. The analyzed DNA profile is then compared to an unknown DNA profile drawn from the Databank.
The first government database (NDNAD) was set up by the United Kingdom in April 1995. The second one was set up in New Zealand. France set up the FNAEG in 1998. In the USA, the FBI has organized the CODIS database. Originally intended for sex offenders, they have since been extended to include almost any criminal offender.
In England and Wales, anyone arrested on suspicion of a recordable offence must submit a DNA sample, the profile of which is then stored on the DNA database. Those not charged or not found guilty have their DNA data deleted within a specified period of time. In Scotland, the law similarly requires the DNA profiles of most people who are acquitted be removed from the database. In Sweden, only the DNA profiles of criminals who have spent more than two years in prison are stored. In Norway and Germany, court orders are required, and are only available, respectively, for serious offenders and for those convicted of certain offences and who are likely to reoffend. Forty-nine states in the USA, all apart from Idaho, store DNA profiles of violent offenders, and many also store profiles of suspects. In 2005 the incoming Portuguese government proposed to introduce a DNA database of the entire population of Portugal. However, after informed debate including opinion from the Portuguese Ethics Council the database introduced was of just the criminal population.
- Combined DNA Index System (CODIS)
- DNA profiling
- Forensic Science Service
- Government databases
- LGC Forensics
- UK National DNA Database
-  "National DNA Data Bank"
-  "National DNA Data Bank"
- Am J Hum Genet. 2008 Mar;82(3):763-71. doi: 10.1016/j.ajhg.2007.12.011. Epub 2008 Feb 14. Phenotypically concordant and discordant monozygotic twins display different DNA copy-number-variation profiles.
- Environmental Science & Research
- "Protection of Freedoms Act 2012: DNA and fingerprint provisions". Protection of Freedoms Act 2012: how DNA and fingerprint evidence is protected in law. UK Government Home Office. 4 April 2014. Retrieved 11 October 2015.<templatestyles src="Module:Citation/CS1/styles.css"></templatestyles>
- CBS News http://www.cbsnews.com/news/supreme-court-says-police-can-take-dna-swabs-after-arrest/. Missing or empty
- Portugal plans a forensic genetic database of its entire population
- 52/CNECV/2007 - Opinion on the Legal System for DNA Profile Databases
- Machado and Silva: Forensic DNA in Portugal