Is there any law on the books that would help us on being falsely accused of something when are findings have proved otherwise? Is there any criminal/civil lawsuit that we could pursue on the people accusing?

This may be informative to you:
http://www.cojocarlaw.com/CM/FSDP/PracticeCenter/Criminal-Law/Criminal-Defense.asp?focus=topic&id=3

First what country are you from,

Are you being accused with a crime by the police or district attorney

Or just being accused by someone at work or a neighbor

Is your wife fasley accusing you of cheating on her

A little more detail

The police and District attroney incorrectly charge people all the time, that is why many are found innocent. ( or at least there is not enough proof to convict them. Unless this is done in an attempt to harm you, little can be done on those. You can merely defend yourself in court.

If someone lies about you and this lie harms or hurts you in some way, you could have a tort (civil) case against them. But you will have a burden of proof as they will.

From the one paragragh you gave I can not tell if any of these apply