Hello group,
Is there a law for posting candid photos?
Do I need a release or can I post any photo of anyone?

from what I understand you can't use them if the faces are identifiable (clear)  without a model release.  UNLESS....they are public figures, stars, politicians etc....these people are exempt because the nature of their job is public and so their image is fair game (my wording, the legal language is different)

If the image is in your book and you can see people in the background I don't think it matters, legal or not, nobody will ever see the shots but the few people that view your book.  If you are putting them on your site you might have an issue.

Eyes must be clearly visible to prove identity-
Must prove damages-
these are words from my attorney.

A lot of this depends on what you're using the images for.

Generally speaking, you need a release if the subject of the image had a reasonable expectation of privacy when the shot was taken. You need a release if the image is used for commercial purposes. You may not need a release in other circumstances.

To help you find your answer, please check Washington Law.

The term you want to look for is called "Right to Publicity"

Very basically it states I have a right to dictate how images of me are used.

Therefore, If you shoot a photo with me in it, that is noticable, I can stop you from using it for COMMERCIAL use.
If you do use it, I can more than likely win a lawsuit against you and take a portion of profits.

Right to Publicity laws are not federal, like Copyright.
Therefore, You must do the research for the place you are taking the photo.

Click here for a discussion on the laws
Washington State Info
ESHB 1074 - Bill for Rights of Publicity in Washington (now Law)

Hope those help.