investigation conducted by HR based on false information created by HR

First please excuse my grammer due to not being a native English speaker.

In October last year HR rep in another state who handles our office and HR manager in NJ(Our coporate office) called and told me that they needed to investigate me and my staffs because of a complaint they received from a senior management in another department (our office has two departments and another department has one senior manager and four group managers). They said they could not explain details of complaint to me, however they said there was a suspision that I am not treating some people equally and since it came from a senior management they needed to investigate further.

Main investigation was how I treat all staffs in my group and I told them that I try to treat everybody equally. They asked me many questions and I was very honest with them. HR rep kept asking about my staff "M" because he said that's the person he wanted to hear most. They interviewed two staffs out of five within a week. I believe they did not interview "B" because she just started to work under me few months ago at that time. They did not interview "M" and "T". All investigation was supposed to be confidential (per HR), however two staff menbers who were interviewed approached me separately and they showed the concern towards me because they did not know why HR was conducting investigation/interview. I was told HR will advise when investigation is done. One month passed, but nothing came from HR.

One day I was talking with a senior management in another department. I knew investigation was confidential, however our conversation ended up with a complaint from his department and found out he had no knowledge of it. He was upset about the fact that he did not know anything about his staff's complaint as a department head and called HR manager in NJ. Right after his phone call to HR in NJ she called and attacked me because I leaked confidential information to him. I have to admit I shared confidential infomation with another manager. Then I asked her back that who was a senior manager complained to HR rep in another state. Her anwer was "I don't know. HR rep in another states has been handling". She investigated me and my staffs with a HR rep without knowing/verifying who actually complained. I was also told that investigation was over few weeks ago, but nobody told me till I talked with HR manager in NJ.

It turned out "A complaint from a senior manager" did not exist. Is anything I can do? Most of discussions were verbal.

By the way the same HR rep had an exit interview three weeks ago with my male staff who was very open to me and left a company for his new opportunity. HR rep told my staff that I sometime lie. Is it legally Ok for HR to say such a comment to my staff(s)?

You may want to firstly jump up the management chain and file a complaint--and ask them to investigate.