Rules 19 and 20 govern the addition of a person as a party to a counterclaim or crossclaim.
Sup. Ct. R. D.C. 13
COMMENT TO 2017 AMENDMENTS
This rule is substantially similar to Federal Rule of Civil Procedure 13, as amended in 2007 and 2009, but maintains two local distinctions-1) a reference to the District of Columbia in section (d), which makes clear that these rules do not expand the right to assert a counterclaim-or to claim a credit-against the District of Columbia or a District of Columbia officer or agency and 2) an exception in subsection (a)(2) and section (b) for counterclaims that are not within the court's jurisdiction.
COMMENT
Identical to Federal Rule of Civil Procedure 13,(1) reference to the District of Columbia has been added to section (d) which provides that these Rules do not enlarge existing legal limitations with respect to suits against the government or its agents and (2) an exemption has been added to sections (a) and (b) for counterclaims which are with-out the jurisdiction of the Court.