A dead fish on a line

Posted by James Briggs on October 04, 2002 at

Another plea for help!
Today I had a request from someone in the US for the origin of 'a dead fish on a line'. He says he 'doesn't here (sic) it much any more', but he believes it to mean foul play. Not only have I no idea about the origin, but I've never heard of the phrase. Any help would be welcome, if only for my own education.