In short, yes. In order to win a case for libel/slander, you need to be able to prove (through evidence, including but not limited to witness testimony), that the speaker made a statement that they either knew of should have known to be false, that this statement or these statements were heard by third parties and that the statement has caused damages (to reputation, earning ability, etc.).
Based on the information that you have provided me, I think you have a strong case, as does your friend, against this individual to win a case for libel/slander.
Moving forward, you need to think about what evidence you can bring forward to prove that these statements were made. It will be easy to prove they are false, one you prove that they have been made by entering into the record copies of your husband and friends NCIC criminal history, which will reflect no felony conviction. The criminal history can be obtained through your state criminal information center.
Let me know if you have any other questions or comments.
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Best wishes going forward!