When Boulder County District Attorney Stan Garnett saw a picture of CBS "48 Hours Mystery" producer Robert J. Halderman in the newspaper, he said to his wife, "This is the guy." Halderman, who allegedly tried to extort money from talk show host David Letterman, visited Garnett's office in Boulder in late July to inquire about Scott Kimball, the suspected serial killer who is expected to plead guilty today to two counts of second-degree murder (via the Colorado Daily). "He pushed us very hard to go on the record at the time and we refused to do that," Garnett (pictured) says. "We felt it would compromise the status of the investigation." Letterman recently admitted on national television to sexual relations with female staffers on the "Late Show," claiming Halderman had threatened to go public unless Letterman paid $2 million. Halderman has pleaded innocent. As for Letterman, the National Organization for Women says his show has created a "toxic environment" for female employees, writes Fox News. So far, though, the scandal doesn't seem to have hurt Letterman. Advertisers are sticking with his show, apparently because his audience has stayed with him, according to The New York Times.