In part 1 of this series I discussed the use of digital forensics as a legitimate science in court for expert witnesses. In this installment of the series I will introduce some research in this article to help drive positive change.
I believe using scientific methods, such as The Supreme Court of the United States (SCOTUS) decided was minimally required in the outcome of the Daubert case, can lead to statistical outcomes of fairer expert answers rather than just the typical three answers of "Yes", "No", or "That's just how computers work" as a conclusion. Introducing the scientific method and statistically based expert answers leaves room for weight between a probability of 0 and 1. A judge or layman jury can use that weight from the statistical outcome for a more informed decision when comparing it to other weights from other tests in the case. It is well known that other forensic sciences such as fingerprinting, drug testing, forensic pathology, DNA testing, and so on use probabilities, so it would not be a great leap to apply it to our newer sciences. Furthermore, in a number of instances other methodologies even use a rate of error which is discussed in the Daubert case. I have yet to personally see others introduce numerical statistics on the record for digital forensics, let alone a rate of error. That needs to change.
This example is a very common question I am asked by clients on nearly any project, especially data loss prevention scenarios and desperately needs to be researched using scientific methods. I wanted to know if I could detect if computer media was wiped. I would also like to know what program was used to wipe the data, if possible. Imagine a situation where an internal employee "went bad" and copied information to a USB memory stick and walked out with the company's crown jewels. The data could be worth billions of dollars and the victim company would most likely litigate. If the same USB memory stick was turned over for examination, would it be possible to detect data wiping? You cannot see what programs were installed on the computer(s) the memory stick was plugged into (because computer(s) were not produced); therefore you do not know if there was a wiping program present. There are many wiping tools available on the internet. It would be near impossible to download every one and try to write a signature for each. That is similar to writing static signatures for every piece of malware which is a nightmare.