Except as provided in subsection (b) of this section, any person may commence a civil action -
No civil action may be commenced -
When two or more civil actions brought under subsection (a) of this section involving the same defendant and the same issues or violations are pending in two or more judicial districts, such pending actions, upon application of such defendants to such actions which is made to a court in which any such action is brought, may, if such court in its discretion so decides, be consolidated for trial by order (issued after giving all parties reasonable notice and opportunity to be heard) of such court and tried in -