2. … but use common sense.
There are certain exceptions to the above generalization, most of them related to a person’s “reasonable expectation of privacy.”
For example, if you’re shooting from a public street into someone’s bedroom or bathroom window, you may be crossing an ethical and even legal line. Shooting under public bathroom stalls or up the skirts of passersby is also likely to get you into trouble.
Texas even has an “Improper Photography” statute that makes it a felony to photograph a subject “without the other person’s consent … and with intent to arouse or gratify the sexual desire of any person.”
If someone waves you off when you try to photograph him or her, you may be well within your legal rights to take the shot, but ask yourself if it’s worth the verbal or even physical altercation that it may yield.
Confrontation aside, I’d always advise being respectful and considerate towards your subjects, and if they express that they’d rather not be photographed, I’d suggest simply moving on.