Video recording somebody in the privacy of their home and broadcasting it without their permission or knowledge.
Even camera don't have to be started remotely. Hey, my camera is always rolling and sending stream to remote server. That's my laptop and that's how I'm using it.
There was no remote activation, there was no spying, there was no nothing. The perp recorded himself, and two month later as Mark was checking his backups he realized the stolen machine was still backuping itself.
Another thought: suppose the thief sold the laptop immediately, and the person recorded is guilty of buying a used laptop.
What it would come down to is reasonable expectation of privacy, but considering the admission that the laptop was stolen, most judges would throw this whole thing out if privacy was the legal argument. Any thief would know that a person whose property was stolen would probably go looking for it.
Mark's first amendment rights to publish data that is recorded on his property trumps the alleged thief's expectation of privacy.
The other issue that could come into play is copyright, but again, Mark is the owner of the property. Photographers who shoot photos on company equipment don't have the copyright of those photos; the publisher does, unless there is a specific contract between the author and the publisher granting the publisher (or the author) reproduction licenses.
Lastly, others have mentioned libel/slander. There's one flaw in this argument: Nowhere in the video description does it a) explicitly accuse the person of being the thief (so if he was found not guilty, the accused has no case there) and do so with malice or b) even make fun of the guy's dancing (which is a statement of opinion and wouldn't hold up in court).
I assume that this was illegal even though the laptop was the school's property
First, the <em>school</em> district <a href="http://www.boingboing.net/2010/02/17/school-used-student.htm... something like 50,000+ photos of minors</a> in their homes and then used what they found in those photos to accuse the minor who sued of doing drugs. The issue question in this case is about who was doing the recording. In this case, it was the school. In Mark's case, the accused knowingly recorded himself (though he didn't know he was also sending that data back to the Laptop's owner).
Secondly, the school's problem was with the scope of what they were recording and where. In your office, your employer can tape you without your knowledge while you're at your desk or at the water cooler, but they can't record you in the bathroom, where you have a reasonable expectation of privacy . You'd certainly have a somewhat subjective expectation in your home, too, even if you were using your work computer. (e.g. The courts would find it reasonable to monitor your Facebook usage on a work computer outside of work hours, but would not find it reasonable to photograph you inside your home from that same computer.)
Lastly, there's the human element of the courts. A judge and jury are almost always going to be less sympathetic toward a school district that should have known better than they would be toward a plaintiff who admittedly took someone's laptop and recorded themselves on it.