After repeated questioning by House lawmakers, Barry Cadden told lawmakers: "Under advice of counsel, I respectfully decline to answer under basis of my constitutional rights and privileges, including the Fifth Amendment."
Federal officials have opened a criminal investigation of Cadden and the NECC.
The Framingham, Mass.-based pharmacy has been closed since early last month, and Massachusetts officials have taken steps to permanently revoke its license.
Inspections last month by state and federal officials found a host of potential contaminants at NECC's facility, including standing water, mold and water droplets. Compounded drugs are supposed to be prepared in temperature-controlled clean rooms to maintain sterility.
Cadden appeared immediately after the widow of a longtime Kentucky judge, who was the first confirmed victim of the outbreak.
Speaking without notes, Joyce Lovelace told lawmakers of more than 50 years of marriage to 78-year-old Eddie C. Lovelace, who was a circuit judge until he died Sept. 17 at Vanderbilt University Medical Center.
She asked lawmakers to implement laws to police companies like the New England Compounding Center, which distributed steroids that tested positive for contamination.
"My family is bitter, we are angry, we are heartbroken and devastated. I come here begging you to do something about the matter."
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