1. Joinder of claims in complaints against the same defendant under R. 18(a).

There must be PJ with respect to each cause of action joined under R. 18(a).

Why? It might not violate due process if a plaintiff had to satisfy PJ for only one cause of action and could join unrelated causes of action against the same defendant without satisfying PJ (assuming that the defendant appeared). But if this were allowed it would invite manipulation by plaintiffs. A plaintiff would concoct an insignificant claim where there was PJ over the defendant in a forum the plaintiff wanted and then would join the unrelated genuine claims he had against the defendant without having to satisfy PJ.

There must be V with respect to each cause of action joined under R. 18(a).

Why? Same worries about manipulation by plaintiffs described above.

2. Joinder of defendants in complaints under Rs. 19 or 20(a).

There must be PJ over each defendant joined.

Why? Anything else would violate the due process clause. The court is asserting power over each defendant and why the court has such power must be justified with respect to each defendant.

All of the defendants joined are counted when one determines whether there is V.

Why? This follows from the language of the venue statute 28 U.S.C. § 1391.

3. Compulsory counterclaims under R. 13(a) against already existing parties.

The counterclaim defendant cannot challenge the compulsory counterclaim on PJ grounds.

Why? It probably would not violate due process to consider the counterclaim defendant subject to PJ. See Adam v. Saenger (F&K 529-30). Furthermore, the counterclaim defendant chose to sue in that forum on that transaction or occurrence (T/O), so how can he complain about being sued in that same forum concerning the very same T/O?

The counterclaim defendant cannot challenge the compulsory counterclaim on V grounds.

Why? It makes sense on V grounds to litigate all causes of action concerning the same T/O in the same forum. After all, the witnesses will overlap. So if the original claim had V, it makes sense to say that the compulsory counterclaim has V.

4. Permissive counterclaims under R. 13(b) against already existing parties.

The majority view is that the counterclaim defendant cannot challenge the permissive counterclaim on PJ grounds.

Why? It does not appear that it would not violate due process to consider the counterclaim defendant subject to PJ. The reasoning of Adam v. Saenger would appear to apply to permissive counterclaims, although whether Adam would be upheld by the current SCt is an issue. Furthermore, the counterclaim defendant chose to sue in that forum, so it is plausible that he should not be allowed to object to that forum as the site for an unrelated suit. This argument is not as strong as the compulsory counterclaim example above, however.

The majority view is that the counterclaim defendant cannot challenge the permissive counterclaim on V grounds.

Why? The argument is that the forum cannot be that inconvenient for the counterclaim defendant or he would not have chosen it as the place for his own suit. Furthermore, there are efficiencies gained from litigating all the differences between the two parties in the same forum, even if they are unrelated. Once again, this is not as strong an argument as it is in a compulsory counterclaim context.

5. Cross-claims against already existing parties.

The cross-claim defendant cannot challenge the cross-claim on PJ grounds.

Why?  It does not appear that it would not violate due process to consider the counterclaim defendant subject to PJ. Furthermore, with respect to cross-claims between co-defendants, if there was PJ over the defendants for the plaintiff's claim against them, there should be PJ for the cross-claim anyway. As for cross-claims between co-plaintiffs, the plaintiffs chose the forum for litigating that T/O, so they can't object to litigating a cross-claim concerning the same T/O there.

The cross-claim defendant cannot challenge the cross-claim on V grounds.

Why? It makes sense on V grounds to litigate all causes of action concerning the same T/O in the same forum. So if the original claim had V, it makes sense to say that the cross-claim has V. Furthermore, with respect to cross-claims between co-defendants, if there was V for the plaintiff's claim against them, there should be V for the cross-claim anyway.

6. Impleaders.

An impleaded party can challenge the impleader on PJ grounds.

Why? Anyone dragged before a forum has a right to challenge that court's asserting power over her.

An impleaded party cannot challenge the impleader on V grounds.

Why? It makes sense on V grounds to litigate all causes of action concerning the same T/O in the same forum. So if the original claim had V, it makes sense to say that the impleader has V. (Note however that an impleader is not exactly about the same T/O as the original claim. It might be about the terms of an insurance contract, for example. Still the two actions are closely related, since the outcome of the impleader depends essentially on the outcome of the original suit.)

NOTE:

I will not consider more complicated joinder scenarios.