In the above case Pleasanton PD supposedly wrongly arrested someone after they had a rifle the police weren't sure was legal or not. According to the person arrested, "Pleasanton police weren’t so sure. “There were multiple cops on the scene, all making phone calls, talking, books on top of hoods, on the back of the cars, everyone’s got paperwork out,” said Haynie.
You would think if they couldn't figure out if it was legal or not they would only take the weapons in the meantime and file a case down the road if necessary. What happened to discretion?
In the end, "the Alameda County District Attorney did not file charges against him, and Pleasanton police paid him back his bail" and issued this statement:
“Following the lawsuit filed by Mr. Haynie et al., the Pleasanton Police Department has taken steps to better educate its officers regarding identification of prohibited assault weapons.” That litigation was promptly resolved between the parties with no admission of liability by any of them.”
Oopsie, and yeah I wouldn't think the supposedly wrongfully arrested person would have much liability.