None of those are reasonable or reliable indications that he/she is lying about having forgotten a password. There are fingerprints or signs of use? What if the defendant has been actively trying to remember the password, or has just done something as simple as moved the laptop's location to get it out of the way? Removable media present? What if it was left in there from when they did have use of the password and didn't have use for the media otherwise? And even if the computer is found on their desk, with the screensaver on, the defendant could have just forgotten the password, it happens and is expected especially if they tended to just barely remember the password before and just happened to forget it at that time.

The fact is, no matter how sure the prosecution is of the accused's guilt and the hard drive's content, the accused can still just have forgotten the password. That's it, just forgotten the password. and the accused could be innocent of the crime, and now facing inescapable prison time, all because they wanted to keep their personal financial documents safe and have an unreliable memory. That is not a reasonable way to carry about justice.