The case is Alhovsky v. Paul, a summary order decided on January 19. Civil rights lawyers know this, but one of the problems with false arrest cases is that the police can get the case dismissed by showing they had probable cause to make the arrest, even if the plaintiff was innocent all along. That's what happened to this guy.
As the Second Circuit (Pooler, Wesley and Chin) summarizes the case,
On June 25, 2006, Alexander Alhovsky rode his bike to Starbucks after working as a clown and magician in Central Park. When he sat down, Alhovsky took off his heavy fanny pack, which contained the balloon pump he used to create balloon animals for children. Unfortunately, Alhovsky forgot his fanny pack on the chair when he left Starbucks. Nearly four hours later, when the employees were closing Starbucks, a manager opened the fanny pack and showed it to a coworker, who promptly threw it onto the sidewalk and called 911 to report a bomb. Two days later, the police, investigating whether Alhovsky had placed a false bomb, saw Alhovsky riding his bike with a similar device strapped to his waist – his back-up balloon pump. Three officers arrested Alhovsky, took him to the precinct, interrogated him, searched his apartment,and released him – a process that took about 4.5 hours from arrest to release.
That's quite a story. But he was charged with placing a false bomb in the first degree. Alhovsky did no such thing, but the police did not know that when they arrested him. It looked like a bomb, and it was unattended for several days. While Alhovsky argues that the balloon pump was inoperable, that does not get him to a jury. A reasonable police officer would think that the balloon pump was likely to cause public alarm or inconvenience and may have been a bomb. That's probable cause, and it also entitles the police to qualified immunity, which gives them the benefit of the doubt in close cases. The Court of Appeals says that the law "applies to the placement of a device or object that looks like, but is not actually, a bomb, regardless of whether the device is 'operable' in some other context."