Io9 has a feature on an interesting and developing legal field: the tort liability associated with injuries to person and property caused by autonomous robots.  This would have been a fanciful discussion just a few years ago, but as the article points out the real-world implications are already upon us:

Lin pointed to the example of home defense robots that are being increasingly used in Asia — including robots that go on home patrol and can shoot pepper spray and paint-ball guns.

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But that said, there are already sentry bots on duty in Israel and S. Korea. What would happen if one of these robots were to kill somebody by mistake? Actually, as Lin informed us, it's already happened. Back in October 2007 a semi-autonomous robotic canon deployed by the South African army malfunctioned, killing nine "friendly" soldiers and wounding 14 others.

With businesses like Amazon preparing to deploy delivery drones and other autonomous systems, and as such technology becomes more affordable and widely-available, this area of law will be of great importance.

The piece can be found in its entirety here: "Who should pay when your robot breaks the law?"