concurring in part, dissenting in part:
In my view, the district court’s grant of summary judgment must be reversed for two reasons. First, the district court granted the defendants’ motion for summary judgment and dismissed Beck’s § 1983 cause of action based in part on its determination that the police officers had probable cause to arrest Beck. This determination was erroneous: the police officers lacked probable cause to arrest Beck as a matter of law. See In re Manuel G., 16 Cal.4th 805, 814-15, 66 Cal.Rptr.2d 701, 941 P.2d 880 (1997).
Second, the district court determined that the officers were immune from liability under Smiddy v. Varney, 665 F.2d 261 (9th Cir.1981), due to the prosecutor’s intervening action of filing a criminal charge against Beck. The Supreme Court’s recent opinion in Hartman v. Moore, 547 U.S. 250, 126 S.Ct. 1695, 164 L.Ed.2d 441 (2006), casts doubt on the district court’s conclusion, at least with respect to Beck’s allegation that the police officers arrested him in retaliation for his exercise of First Amendment rights. Beck had attempted to rebut the Smiddy presumption (i.e., the presumption that a prosecutor’s filing of criminal charges constitutes an exercise of independent judgment that immunizes investigating officers) by showing that the police officers unduly pressured or deceived the prosecutor. See Smiddy, 665 F.2d at 266-68. However, Hartman indicates that the prosecutor’s intervening action will not immunize the police officers from a First Amendment retaliatory arrest claim if Beck can establish that the police officers lacked probable cause and had a retaliatory intent. 547 U.S. at 265, 126 S.Ct. 1695. Because the district court did not have the benefit of Hartman, and thus did not apply the correct test to Beck’s First Amendment claim, we must reverse the grant of summary judgment in favor of the defendants. I agree with the majority to that extent, and join in Sections I, II A (excluding the majority’s holding), II B, paragraphs 1, 2 and 4 of Section II D, and Section II E 1.
However, in my view, it is not appropriate to go further and address issues neither briefed to nor decided by the district court. Although a First Amendment claim was lurking in Beck’s complaint, the parties did not discuss it and the district court did not address it. By the same token, the parties did not develop their arguments on this key question whether the record raised a material issue of retaliatory intent on the part of the police officers. It is inappropriate for us to reach this mixed issue of law and fact for the first time on appeal in the absence of development by the parties or a ruling by the district court. See Singleton v. Wulff, 428 U.S. 106, 120, 96 S.Ct. 2868, 49 L.Ed.2d 826 (1976) (“It is the general rule ... that a federal appellate court does not consider an issue not passed upon below.”).
Nor should we reach the question whether the Smiddy presumption immunized the police officers from liability under Beck’s Fourth Amendment false arrest claim. The district court had concluded that the police officers were immunized under Smiddy because Beck had failed to show that the police officers unduly pressured or deceived the prosecutor. Rather than address the district court’s ruling, the majority rests its determination that the Smiddy presumption does not immunize the police officers from Beck’s Fourth Amendment false arrest claim on a new ground: the *874Smiddy presumption fails because the prosecutor raised the attorney-client privilege and refused to answer some of Beck’s questions. See maj. op. at 869-70. But neither party raised this argument even on appeal-it appears for the first time in the majority opinion. In my view, it is inappropriate for the majority to decide a key issue on an un-briefed rationale sua sponte, without giving the defendants any opportunity to rebut the majority’s reasoning. See Hartmann v. Prudential Ins. Co. of Am., 9 F.3d 1207, 1214 (7th Cir.1993) (Posner, J.) (“Our system unlike that of the Continent is not geared to having judges take over the function of lawyers, even when the result would be to rescue clients from their lawyers’ mistakes.”).
“Our judicial system generally assumes that consideration of an issue at both the trial court and appellate court level is more likely to yield the correct result, because the issue will be more fully aired and analyzed by the parties, because more judges will consider it, and because trial judges often bring a perspective to an issue different from that of appellate judges.” Ecological Rights Found. v. Pac. Lumber Co., 230 F.3d 1141, 1154 (9th Cir.2000). In the interest of fairness to the defendants and deference to the district court, I would reverse the district court on the narrow grounds explained above, and remand this case for further proceedings.