2) What happens in these breaking-and-entering raids if the homeowner surprises the burglar and kills him? Is a homeowner supposed to somehow know that the person sneaking around his home has a secret warrant signed by a secret judge in a secret courtroom?
Interesting legal question there, Tim. IANAL, but I would imagine that the "reasonable man" test might be the most important factor. That, and the prejudices of the court. I'm sure that those of us who AAL could give a better answer. However, I don't think it would ever come up. Obviously, the FBI knows that an operation like this would be highly dangerous, for both their agents and the suspect, if your scenario above ever happened. They have plenty of resources. I imagine that they do surveillance on the place and the person quite extensively before they go in. They know that the suspect is out of town, or at work, or with his mistress when their breaking-and-entering team is working. They probably also have a team watching the suspect/homeowner while their other team is in the residence. If the surveillance team sees that the suspect is suddenly returning home, they can alert the breaking-and-entering team to get the hell out. I imagine that the surveillance team would do whatever is necessary to make sure that the homeowner/suspect doesn't get back while the breaking-and-entering team is in: they could have a car accident with him, have a local cop pull him over and take plenty of time writing the ticket, they could have a beautiful woman strike up a conversation with him, many possibilities. I'm sure they have a list of options ready to go in this scenario. So I think the risk is very low, and I'm sure they play it conservatively on these types of operations. So don't worry about finding any of these guys in your house, because you won't! But if you do, offer them a beer! They word hard. Oh wait, they're probably Mormons. Offer them a lemonade to be on the safe side.