How can I protect myself in this situation?

Much more information is needed in order to answer your question. What's not clear is what type of job/profession you have, type of facility you work in, the accusations against you, whether there was an investigation/inquiry, whether the client was actually discharged involuntarily or is still in the facility, whether you are on a paid or unpaid leave of absence, and the length of your leave of absence.  If you are on an extended unpaid leave of absence and you can prove the client lied, you may have an action for slander against the client.  The statute of limitations is one year from the time of the slander, so keep that in mind. Depending on where you are employed, there should be procedures in place for investigating the conduct of which you were accused, and your employer is responsible for following those procedures and conducting an investigation. If the procedures were not followed and that results in loss of salary, and you can prove that had the procedures been followed you would have been exonerated, you may also have an action for money damages against your employer.