Whom is a diversity statement written for?

The purpose of having a diversity statement is that you can honestly say that you have one if anybody asks.

The people who will read them would include:

• People who are told they have to read them.
• People who have nothing better to do.
• People who want to confirm that you really do have a diversity statement.

Don't assume that anybody takes any relevant decisions based on the diversity stament. The people who make decisions will either continue to be fair to all candidates, or will continue to be prejudiced. Writing a diversity statement won't change that.

It depends on how serious the university you are appliying for is in encouraging diversity.

In every case, the persons responsible for diversity / minorities / ... will read it and bring in their opinion.

I'm sure, at my institution every person in the selection committee will read it, and it will affect the decision. If your research record or teaching performance are not good, the diversity statement will not save you. But if there are two people with similar performance, it will make a difference!

Some insitutions are haveng point based evaluation sheets for applicants - it is up to then to decide how strong the influence of the diversity statement is. But usually those factors are not public.