Yet when computers are involved, they automatically take everything. New forensic methods need to be developed to provide proof that neither the police nor defendants have tampered with computer evidence such as hard disks and storage media. Defence specialists like Sommer worry that current practice is very variable, and usually depends on proprietary gadgets and software whose inner workings are withheld from courtroom scrutiny and independent scientific testing. The computer raid team will automatically copy and take reams of confidential medical or privileged legal information. At present, the law provides no special safeguards to stop such information being abused, or to protect the third parties whose private information has been obtained.
Arguments can be as basic as to whether the copies made by the police are authentic.
One standard police forensic procedure is to make multiple copies and seal them, giving one set to defence lawyers. Another is to cryptographically sign the CD-Rom copies. If you're under investigation by private detectives, the first thing they will do is remove and sift through your rubbish bags. Private disk investigators are no different. The first place they'll look is in the garbage left on disk.