Would that possibly run afoul of "inciting imminent lawless action"? I would also love to see such an advertising campaign, but I suspect you would get some pretty fierce and heavy-hitting push-back on it.
You mean, the media would start running your ads for free?
Here is a somewhat related ad campaign, encouraging people with jury duty to refuse to convict people for crimes without victims: http://www.washingtonpost.com/local/crime/metro-billboard-ad...
They tried to get this guy for jury tampering: http://www.nytimes.com/2012/04/20/nyregion/indictment-agains...
Those campaigns managed to ruffle some feathers, and got lots of media attention because of it. I imagine that this propose whistle-blower campaign would raise even more.