Conservative political entities who supported Wisconsin Governor Scott Walker are being subjected to a secret investigation. Special Prosecutor Francis Schmitz has issued a series of subpoenas to 29 conservative groups, demanding that they submit all documentation related to the recall campaigns mounted by unions and their supporters against Walker in 2011 and 2012. The investigation is being conducted under the auspices of the state’s John Doe law, which forbids the targets of subpoenas from revealing the contents of those subpoenas to anyone other than their lawyers. The effort reeks of political intimidation. According to the Wall Street Journal, the two...