MEMORANDUM **

Plaintiffs appeal a defense verdict following a four-day jury trial. We have jurisdiction under 28 U.S.C. § 1291 and affirm the judgment.

1. The district court did not abuse its discretion in denying plaintiffs’ proposed jury instruction. The district court’s instructions were consistent with our holding in Dawson, where we held that an officer may detain a building’s residents during a search “so long as the officer conducts the detention in a reasonable manner.” Dawson v. City of Seattle, 435 F.3d 1054, 1066 (9th Cir. 2006); see also Muehler v. Mena, 544 U.S. 93, 98, 125 S.Ct. 1465, 161 L.Ed.2d 299 (2005) (“An officer’s authority to detain incident to a search is categorical; it does not depend on the quantum of proof justifying detention or the extent of the intrusion to be imposed by the seizure.” (internal quotation marks omitted)).

2. The district court did not abuse its discretion in denying plaintiffs’ request— raised midway through trial—to amend the pleadings by adding a Fourth Amendment claim based on the allegation that plaintiffs did not receive a copy of the search warrant. See Fed.R.Civ.P. 15(b). The defendants would clearly have been prejudiced by having to defend against this newly-minted claim.

AFFIRMED.