The U.S. military might be guilty of murdering civilians on the high seas. Attacks on alleged drug boats in the Caribbean Sea and the Pacific Ocean demand extraordinary public investigation into any wrongdoing, not whispered consultations in the halls outside a congressional subcommittee room. Calling for federal lawmakers to investigate something feels almost quaint in our time of extreme partisanship and congressional ineffectiveness. But the past shows that Congress has ample powers to scrutinize, expose and end government abuse — if its members use them.