Dr. Craig Jerner Dr. R. Craig Jerner, Ph.D., PE specializes in accident investigation and metallurgical failure analysis, with over 30 years experience as a metallurgical consultant and accident investigator. He has testified as a metallurgical expert in over 250 depositions and more than 70 court appearances. If you or someone you know should need the services of  Dr. Jerner and J.E.I. Metallurgical, Inc. please visit our web site at the buttons below.