On the first day that Constellation Energy Group could file a lawsuit against the state alleging the unconstitutionality of $386 million in credits to ratepayers, Maryland beat them to the punch.

Attorney General Douglas Gansler filed the lawsuit Friday in Baltimore City Circuit Court against Constellation and its subsidiaries Baltimore Gas and Electric and Calvert Cliffs Nuclear Power Plant, seeking a ruling on the constitutionality of the credits ordered by 2006 legislation.