Authorities say Mississippi’s deputy medical examiner is under investigation after relatives of a black man found hanging questioned his credibility over allegations he lied in a death report while working in Africa.

The Mississippi Department of Public Safety said Monday it’s investigating allegations that Dr. Adel Shaker lied about the cause of death of a murdered British tourist when he was working in Kenya.

The allegations were raised by a lawyer for relatives of Fredrick Jermaine Carter, who was found hanging in a tree near Greenwood in December. Authorities say Carter had a history of mental illness and suicide attempts and killed himself. His family isn’t sure and wants Shaker’s complete file on the case. Attorney Valerie Hicks-Powe says he won’t give it to them.

Shaker hasn’t responded to messages.