A friend of mine got into an argument with a guy, so he disconnected the guy's satellite TV cable wire on the outside of the guy's house. He claims he wouldn't get in trouble if caught, and I think he would at least be guilty of a misdemeanor. who's right?
In California, it is actually a felony for someone to do that. Your respective state may have a similar law. You can look up your state law at http://www.findlaw.com/.
Penal Code Section 591. A person who unlawfully and maliciously takes down, removes, injures, or obstructs any line of telegraph, telephone, or cable television, or any other line used to conduct electricity, or any part thereof, or appurtenances or apparatus connected therewith, or severs any wire thereof, or makes any unauthorized connection with any line, other than a telegraph, telephone, or cable television line, used to conduct electricity, or any part thereof, or appurtenances or apparatus connected therewith, is punishable by imprisonment in the state prison, or by a fine not exceeding five hundred dollars ($500), or imprisonment in the county jail not exceeding one year.