What is the test for "capable of repetition" in a police chokehold case?

The question then is whether the practices to which appellants object are capable of repetition as to them. Where no class action has been instituted, the capable of repetition doctrine is applied only in exceptional situations where the plaintiff can reasonably show that he will again be subject to the same injury. See City of Los Angeles v. Lyons, 461 U.S. 95, 108, 103 S.Ct. 1660, 1668, 75 L.Ed.2d 675 (1983) (unlikely that plaintiff will again be subject to police chokehold). That other persons may litigate a similar claim does not save a case from mootness. Lane v. Williams, 455 U.S. 624, 634, 102 S.Ct. 1322, 1328, 71 L.Ed.2d 508 (1982) (question whether defendant must be informed that guilty plea yields mandatory parole term is moot where sentence already served; petitioner now knows consequences of plea).