What is the test for remand for damages for a Fourth Amendment violation?

remainder of Plaintiffs' asserted claims, which the jury consequently rejected. We therefore remand for a new trial to determine damages for the Fourth Amendment violation as well as any issues raised by Plaintiffs' remaining claims. See Brooks v. Brattleboro Mem'l Hosp, 958 F.2d 525, 530 (2d Cir. 1992) ("It is well established that a partial new trial may not properly be resorted to unless it clearly appears that the issue to be retried is so distinct and separable from the others that a trial of it alone may be had without injustice.") (internal quotation marks omitted).