Dr. Howard Gregg Diamond is the operator of Diamond Back Pain and Wellness Centers in Paris and Sherman. A federal grand jury indicted Dr. Diamond on multiple charges related to writing prescriptions for controlled substances without a medical purpose. U.S. Attorney Brit Featherston links Dr. Diamond to seven overdose deaths in Sulphur Springs, McKinney, Hugo, Idabel, Yukon, Abilene, and Ardmore. The doctor pleaded not guilty to all charges. There is a detention hearing scheduled for Friday.