Who is Marty Roberts from Next and what is their importance?

Marty Roberts is the medical examiner at Long Beach Memorial. When Tom Weller's father dies, his body comes to the morgue that Marty Roberts runs. Roberts assistant makes the mistake of allowing Tom Weller's sister take blood from her father in order to run a paternity test. When the Weller family threatens to sue, Roberts is the one who appears at the exhumation to oversee the retrieval of tissue for further DNA testing. During the exhumation, Roberts discovers that his assistant has taken the long bones of Weller's arms and legs and replaced them with metal pipes.