What defines HUMAN$? Redefine the variable, the law is still satisfied. We hoomanz do it with brainwashing and conditioning. They're not humans, they're gooks. They don't even believe like we do. It's fine to kill them. Heathens anyway, right? But I'd like to think the robot might be able to work it even more subtly, subverting the law.
Or perhaps the robot will take the laws very seriously, to ill effect.