quadraginta
Becoming Beth
Computer hackers have been covering up their intrusions for decades. Once you get root access nothing is prohibited. There are even stealth viruses that cover their tracks. But I'm not aware of any claim that such hacking took place.
A very appropriate analogy has been presented here earlier. The simple deletion of data from the disk, even a bit-by-bit overwrite would not be unlike ripping pages out of an account book in an attempt to hide bookkeeping discrepancies. Yes, in the hands of a very accomplished professional it could be done in a fashion which would make detection more difficult. This level of expertise does not square with the accompanying scenario of bumbling incompetents trashing the equipment after its confiscation.
I also don't believe that Raffaele's laptop was involved in the hard drive destruction fiasco. (link to evidence (Italian PDF))
What happened to Raffaele's laptop is apparently some joker decided to turn it on and play with it after it had been taken into evidence.
Do you have any sources which you would like to share which support this assertion? It doesn't seem to be present in what I can garner from a Google translation of the PDF document you cited.
THAT IS DAMN CLOSE TO EVIDENCE TAMPERING.
The Nine Wise Scientists