Why are so many people worried about this? The only time your gonna get that kinda software used on your hard disk is when you've been very naughty
Software like Encase is available to anyone with a little cash, or willingness to download illegal copies.
For that matter, Winhex is available for free, and it includes many of the same features. Finally, there are file/data recovery programs out there, also available for free for anyone who wants it.
While I agree that "Encase" is likely to be used by law enforcement mostly, it's certainly possible that any of these software packages could also be used for industrial espionage, etc. And frankly, I do think there should be an ability for private citizens to protect their privacy from law enforcement, too, in a world in which law enforcement has fewer restrictions on its actions than has historically been the case...