§ 31102. Waiver of immunity
(a)
In General.—
A civil action in personam in admiralty may be brought, or an impleader filed, against the United States for—
(b)
Counterclaim or Setoff.—
If the United States brings a civil action in admiralty for damages caused by a privately owned vessel, the owner of the vessel, or the successor in interest, may file a counterclaim in personam, or claim a setoff, against the United States for damages arising out of the same subject matter.