Is it legal to confiscate the film from a camera belonging to someone who randomly takes a photograph of you?

nope ... that's called theft ...

Not even the police have the authority to confiscate your film or ask you to delete picture from your digital camera. If you are on public property you may take pictures of aything you wish. OTOH, if you are on private property that has been posted "no photographs allowed", or something to that effect, you may be asked not to take pictures.

Photos taken on sensitive government facilities may get you a visit from the FBI.

No, and the photographer has every right to defend his property - using force if necessary.

No if your in public. Yes if your in a privet place such as a bathroom.

It would depend on the country or state.

"Sometimes agents acting for entities such as owners of industrial plants and shopping malls may ask you to hand over your film. Absent a court order, private parties have no right to confiscate your film. Taking your film directly or indirectly by threatening to use force or call a law enforcement agency can constitute criminal offenses such as theft and coercion. It can likewise constitute a civil tort such as conversion. Law enforcement officers may have the authority to seize film when making an arrest but otherwise must obtain a court order."
Source and further information:
http://www.cob.org/documents/mayor/eob/legal-rights-of-photographers.pdf

Please notice that some people might prefer in some cases to confiscate a film, even with the use of force, because they prefer to assume the consequences of doing an illegal thing rather than have those photos published.

In many cases, they could first ask you politely to give them the film (or erase the digital file).

Of course not. And what does this have to do with "Civil rights law"?

I don't know exactly but it seems to me that if someone confiscated the reel of film just because they appear in one picture,then surely they are guilty of the theft of the rest of the film!!! +3

If you are in a public place, and they are in a public place, they cannot confiscate your film unless they have a court order of sorts.
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However everything changes if you are not in a public place. If you took photos of them while they were in their bathroom, for example, they could have the photos confiscated, ad could probably get financial compensation from you.

Nope.
That's called theft.

There is nothing illegal about taking pictures of people so long as you aren't invading their privacy to do so.