In Nieves v Bartlett, the Supreme Court holds that plaintiffs alleging retaliatory arrests are generally required to prove a lack of probable cause to arrest; there is one small exception for plaintiffs who can demonstrate by “objective evidence” that similarly situated individuals would not have been arrested but for the protected speech at issue. Unfortunately, neither the general rule nor the exception in this recent ruling will help many victims of retaliation. The expansion of the criminal code to cover petty indiscretions means police officers will not have any difficulty identifying probable cause to arrest for something. As to the Nieves exception, obtaining records of arrests that did not occur requires proving a negative—never an easy task. Importantly, the opinion requires courts to disregard even credible evidence of retaliatory intent at the threshold level, unless the plaintiff can show lack of probable cause or provide evidence regarding similarly situated individuals.

As Justice Neil Gorsuch tentatively suggests in his Nieves opinion, the rule from United States v Armstrong, which governs the discovery bar for selective prosecution claims, is a much better fit than the Nieves majority’s rigid rule. Although the Armstrong Court crafted an analogous similarly-situated-individuals requirement, the opinion left open whether direct evidence of intent could allow litigants to sidestep that requirement. Given the centrality of intent to both selective prosecution and retaliatory arrest claims, courts should follow Armstrong in the retaliatory arrest context and consider evidence of intent at the start of litigation. While evidence of prosecutorial intent rarely comes to light, retaliatory arrest plaintiffs will have significantly more access to evidence of police intent, making the Armstrong rule more useful in this context—especially in the age of cellphone videos and civilian vigilance.