Is it a crime for an investment person to do what is called "churrning" with the money you have trusted them with?

Yes, but that's like asking if it is illegal to do something illegal, because churning, by defintion, is illegal.  The question is whether the investment advisor engaged in churning, the basic defintion of which is that the advisor engages in numerous trades, regardless of whether those trades are in the client's best interests, in order to generate more fees for themselves.