One thing I would do is require every chair or dean to have a consultation every two to three years to review all the salaries within a unit to make sure that, when assistant professors who are coming in are getting better salaries by virtue of the negotiated agreement, there isn't an inequity for the assistant and associate professors. Those associate professors, from what they call the “sandwich” generation, are primarily women, including women who, for example, took time off to have their children. Once you do that, you are almost always already behind—and not because of your knowledge or qualifications or experience—in terms of the salary gap.
I would say that it would be a requirement to have regularized reviews of all salaries by chairs, deans and the provost, but the administrating body would be HR. I keep coming back to HR for this.