With higher electricity rates looming, the Maryland legislature voted Thursday to delay the planned $11.4 billion merger of Constellation Energy Group Inc. and FPL Group Inc. until a special counsel reviews the deal. Even after that examination, lawmakers would have authority to stop the merger.

Unless the bill is vetoed by Maryland Gov. Robert L. Ehrlich, the legislation puts the merger of Constellation and Juno Beach, Fla.-based FPL, parent company of Florida Power & Light Co., on hold until next year.