MADISON, Wis. – In the nearly two years since the Democrat-led Milwaukee County District Attorney’s office launched its second secret “John Doe” investigation into Republican and other political opponents, legal observers say they still don’t know exactly how such probes work.

Though gagged by court order, several sources have told Wisconsin Reporter the manifold legal attack on nonprofit political organizations has included dramatic pre-dawn raids on homes and offices; confiscated equipment and files; and demands for private phone, email and other records.

While some conservatives have spoken out, much of the investigation remains hidden from public scrutiny. But perhaps one of the biggest secrets is just how presiding judges and special prosecutors are selected to run and referee the John Doe probes.