After reading the law, it actually seems to be a clear violation. He is not a party in the court case so presumably his testimony is that of an expert witness.

After reading the law, it actually seems to be a clear violation. He is not a party in the court case so presumably his testimony is that of an expert witness. Providing expert testimony as an engineer sounds an awful lot like practicing engineering. He is not licensed and he is not practicing under the aegis of a licensed firm. He's in violation of the law.