No former employee of the department or member of the attorney general's staff may at any time after severing his employment with the department or the attorney general appear in a representative capacity on behalf of other parties in a formal proceeding wherein he previously took an active part as a representative of the department as provided by RCW 42.22.040.

[Regulation .08.050, effective 3/6/61; Regulation .08.050, effective 3/23/60.]