The Philadelphia Inquirer’s witness intimidation series (previous post here) triggered a congressional hearing. You can read the testimonies here, including criticism of the series for exaggerating the extent of the problem. See testimony of Michael Coard. Senator Arlen Specter (D-PA) subsequently called for a law that would make witness intimidation a federal offense; witness intimidation is already a state crime. Story here. In a similar development, Rep. Elijah Cummings (D-MD) introduced the Witness Security and Protection Grant Program Act of 2009, to provide assistance to state and local witness protection programs. Press release here. More indications that the law of informant use will look very different a few years from now.