“This is insane.” Those are the words of Sen. Patty Murray, who has seldom raised her voice during 17 years on Capitol Hill. So what provoked such outrage? A finding by the National Women’s Law Center that in eight states, plus the District of Columbia, it’s legal for insurance companies to deny health coverage to women victimized by domestic violence.

Murray, a Washington Democrat, was talking about a problem that, while important, affects relatively few women. Her charge of insanity could apply to a much larger issue as well: the finding by the law center that all women who buy insurance in the private market regularly face “huge and arbitrary” penalties compared to men.

Michelle Obama, a former hospital administrator, raised this point recently at a White House meeting: “It’s clear that health-insurance reform and what it means for our families is very much a women’s issue.” The fact that insurance companies are free to practice gender discrimination “is still shocking to me,” she said. “These are the kind of facts that still wake me up at night.”