Family of executed Ohio inmate sues expert witness who testified about lethal injection

The family of a condemned Ohio inmate put to death during a prolonged execution has sued the state's former expert witness on lethal injection.

The lawsuit, expanded from an earlier filing, alleges that Dr. Mark Dershwitz knew that inmate Dennis McGuire would suffer during the January execution but helped create the state's new lethal injection policy anyway.

The new complaint filed in federal court earlier this month says Dershwitz also provided medical and scientific advice to the state prisons agency.

Dershwitz, a University of Massachusetts anesthesiologist and pharmacologist, announced in June he would no longer act as an expert witness for states defending their lethal injection methods.

Dershwitz said he couldn't immediately comment.