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"more controls are needed"
Including, but not limited to:
a) only serious criminals should be on the register -- civil, motoring and public disorder offences should be exempt. Probably it should be restricted to those serving a prison sentence. And certainly, those not convicted of any crime need to be removed from the register, automatically and without formality unless specifically ordered by a court to remain on the register.
b) whenever an investigation involving DNA is carried out, every person involved should be reminded of the ease in which the criminal could have planted another persons DNA at the scene or the DNA could be present for innocent reasons.
c) Nobody should be arrested, questioned, accused or otherwise publicly mentioned or their premises searched solely on the basis of DNA evidence. It can be used as a reason to look for other evidence, but all further investigation should proceed solely on the basis of that other evidence.
d) In a court case, any DNA "evidence" should be considered inadmissible as evidence and should not be presented to the court. If there is no other compelling evidence, then the case should not be brought.