Evidence of Twitter Shadow Banning Users

Recently it has been made known something that twitter users have long suspected. That Twitter would "shadow ban" or "ghost ban" certain users based on their tweets or political viewpoints. We want proof and are willing to pay for that proof. Provide documents or evidence that twitter is engaging, or has engaged, in the user of shadow or ghost banning users. Must be clear evidence of the company doing this to users, either presently or historically.