Key senator defends nuclear commission chief

Washington (CNN) – A key Senate Democrat came to the defense of embattled Nuclear Regulatory Commission Chairman Gregory Jaczko on Thursday after his four fellow commissioners sent a letter to the White House criticizing his leadership. They also testified before a House committee that Jaczko had "bullied" staff, restricted access to information and quietly assumed emergency powers following the Fukushima Daiichi nuclear disaster in Japan this year.

Sen. Barbara Boxer of California called a Wednesday House hearing a "witch hunt and an attempt to assassinate the character of a dedicated public servant," namely Jaczko. "Frankly, I was shocked, and I was appalled," she said.