Tiredofgaggs has a good point.
i have a spell or two to help with a court case, but to forget, i'm not sure. personally, you made your bed, now lie in it [don't know if it's your fault or not, just saying] the way the threefold law works, you made a mistake, you need to suffer the consequences. i know that's not always the case, some vindictive person could be doing something because they don't like you, i don't know this. uma no hone as it were [Japanese idiom, basically means unknown background and/or little detail]
you could try a honey jar spell to make the person soften up and decide not to press charges. but if the unlawful act has not been committed, i'd simply not go through with it.