(a) Except as otherwise provided by constitution or statute or by these or other rules promulgated by the Supreme Court of this State, no person has a privilege to:

        (1) Refuse to be a witness;

        (2) Refuse to disclose any matter;

        (3) Refuse to produce any object or writing, or

        (4) Prevent another from being a witness or disclosing any matter or producing any object or writing.

    (b) Nothing herein shall be construed to confer a privilege otherwise limited by statute.