The Dodge County sheriff says an investigation into a reported death at the Waupun State prison in the 1960s centers around accusations that an inmate was beaten to death by a correctional staff member. Sheriff Pat Ninmann says a former inmate at the prison contacted her earlier this spring to say he witnessed the incident nearly 50 years ago. Ninmann says information from the former inmate led investigators to the correct documents. She says investigators have been able to narrow the list of possible victims to about nine inmates who died in the time frame outlined by the informant. So why did the former inmate wait this long to come forward? Ninmann says the man told her he wanted to clear his conscience.