<human>: Could you distill the essence of the text into 1-3 sentences?

Hello all!

Throwaway for anonymity. 

I am here because I go to a music school (very expensive, private, not state) and many of the players in my studio have been very upset with our studio professor. He is, overall, not a good teacher, and is often a bad person. We are currently unsure of whether or not we want him fired, but we are positive that his behavior won't change if/when he gets talked to by the administration.

He makes racist/sexist/otherwise discriminatory comments to us individually and in groups, and is constantly talking about his students to others (gossiping, if you will) and also spending a lot of time checking emails in our lessons rather than actually teaching us.

A group of us met with the associate dean today, and we voiced our concerns. However, due to the rigorous and legal process this may be, there must be solid and concrete proof of the things he says, otherwise it's our word against his.

So I guess this is where my question becomes twofold:

The first is, and I would have to check the university's rules on this as well, at what point does a verbal statement become accepted as fact? Even though there is no solid evidence, if you have 6 people going in and saying the same thing about a prof, how does that not hold any weight?

Second, many of us would like to record our lessons. However, with him knowing that we are, he will be very careful. He is very careful with the freshmen and people in a professional setting, but he is a dick to the upperclassmen and isn't afraid to show his "true self."

I read that Ohio was a "single-party" law state, meaning only one person in the party needs to consent to a recording of a private conversation, in this case a lesson. We were also told that it is illegal to record somebody without their knowledge or consent.
<bot>: we want to gather evidence of a professor's lack of teaching and general morality in the most legal way possible, including recording.