New York Attorney General Eric Schneiderman’s investigation of Exxon Mobil for climate sins has collapsed due to its own willful dishonesty. The posse of state AGs he pretended to assemble never really materialized. Now his few allies are melting away: Massachusetts has suspended its investigation. California apparently never opened one.

The U.S. Virgin Islands has withdrawn its sweeping, widely criticized subpoena of research groups and think tanks. In an email exposed by a private lawsuit, one staffer of the Iowa AG’s office...