1
general::
Phrase(s): have clean hands
Fig. to be guiltless. (As if a guilty person would have dirty or bloody hands.) • Don’t look at me. I have clean hands. • The police took him in, but let him go after questioning because he had clean hands.
McGrawhill's American Idioms And Phrasal Verbs
2
general::
Be innocent or guiltless, as in John's got clean hands; he had nothing to do with it. It is sometimes worded as one's hands are clean, meaning "one has done nothing wrong," as in Don't look at me? my hands are clean. This metaphor for freedom from wrongdoing dates back to at least 1600.
American Heritage Idioms