In a recent trial, an alleged speeder was acquitted and awarded AU$3,300 when the Roads and Traffic Authority couldn't prove that the evidence produced by a traffic camera was untampered with. The problem lies in the use of the MD5 encryption algorithm to store the time, date, speed, place and licenseplate of the offending vehicule caught on camera.
Chinese scientists had produced proof that it is perfectly possible to alter the protected data - for instance increase the speed - and still end up with the exact same MD5 key. Thus, having an MD5 key doesn't prove the data itself is authentic, nor that it hasn't been tampered with.
Security and encryption is good, but it can (and will) be used against you if you don't keep up to date and rely on it never being broken.
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