Re: Photography in the US
From a legal standpoint, in the United States, if I can see it from a public location, I can shoot it with very few restrictions; military bases and some government buildings can be exceptions. I also don't worry about people (children) in my shots; it's never been an issue for me except for the occasional request that I send copies via email which I'm always happy to do. People in public are fair game, period. No model releases are required. If you're out in public you can be photographed. Reasonable expectation of privacy applies, however, so I can't shoot from the street into someone's bedroom for example. Kids playing in a park is a good shoot, but someone using the ATM is not.
If I'm on private property, and I'm asked to refrain from taking photo's by the property owner, I'm legally obligated to do so. If I'm on public property I can legally shoot private property if it's in plain view.
Places like military bases and other government buildings typically do not allow photography inside their perimeter. Photographing such locations from a public vantage point can also be prohibited. It's best to avoid shooting them specifically, but if they happen to wander into my shot I don't worry about it and I've never had a problem (and I live in a heavily, military-popular area).
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