Digital evidence can be immensely valuable in a court case, but if it is to be effective, it requires protection. There must be a trail showing how this type of evidence was handled, for what purpose and by whom.
If there is any compromise of the digital evidence, it could damage the entire investigation. One way to preserve and protect it is through the use of digital hashing.
The protection problem
Law enforcement personnel must maintain a chain of custody for digital evidence, just as they do for any physical evidence. Types of evidence include not only electronic documents, but also digital video and photos as well as hard drive contents. It may be possible to alter, delete or even fabricate unprotected digital evidence.
What bothers courts
A study by the RAND Corp. and other participating organizations found that courts are wary of digital evidence for the following reasons:
- Law enforcement officers may not know how to secure it
- There may not be enough department personnel to handle the volume of incoming digital evidence
- Judges may not be sufficiently well-informed about the best use of digital evidence in a court of law
Digital hashing is a way of creating a digital fingerprint of the evidence in question. It uses algorithms to make a digital impression that is unique to a particular digital record. Any change made afterward – a single period, for example – will create another unique hash. Therefore, the new copy will not match the original, a clear sign of tampering.
At a time when those who are intent on defrauding others often use technological advances, preserving digital evidence of wrongdoing is critical, but it works either way. If the protection of evidence has been sloppy, a criminal defense attorney can take apart a case about some form of white-collar crime by merely raising issues that point to tainted evidence. On the other hand, digital hashing may effectively secure evidence that will win the day for someone wrongly accused of fraudulent activity.