It’s simple: approach a celebrity, don’t expect the interaction to be private. That’s one takeaway from a decision by the U.S. Court of Appeals for the Seventh Circuit in Chicago, affirming  the dismissal by a U.S. District Court in Madison, Wisc., of a lawsuit aimed at comedienne Joan Rivers.

As described in the suit, a woman came up to Rivers after a comedy show and conversed with her for all of 16 seconds. That chat was taped and included in a documentary about Rivers. Apparently displeased with her portrayal in the doc, the woman sued for invasion of privacy and misappropriation of her image.

U.S. Circuit Judge David Hamilton agreed with the lower court’s finding that any reasonable person who comes up to a celebrity after a public performance would anticipate an encounter with security, not to mention cameras in this case. Indeed, security was nearby and the cameras were rolling, thus, the woman had no expectation of privacy when she approached Rivers.

Further, this scenario fits into the newsworthiness exception for misappropriation of image claims, because Rivers’ fame renders the documentary a matter of public interest. This decision falls in line with other unsuccessful suits brought by disgruntled individuals shown on film, including one against Sacha Baron Cohen aka Borat. As Hamilton stated, if this exception were triggered for a documentary about a fictional character, it certainly should be for a film about a real celebrity. The court added that consent forms for films such as Cohen’s and Rivers’ are of no legal significance, but rather, are done out of “extra-special caution.”

The legal lesson here is that individuals should use caution in approaching celebrities, especially if there are cameras present. Even if they are not present, suits will still not likely get beyond a motion to dismiss. So long as the use is relatively short (16 seconds here, 13 seconds in the Borat case, 4 seconds in the Supersize Me case), filmmakers should feel comfortable including non-famous individuals in their films without needing to get signed consent.