They didn't copy a damned thing. They were only inspired by someone else's work which influenced they way in which they created a new work - the same way all creation happens on some level.
For that, they must now stand trial.
The court will try and tell you that the Defendants here have "copied" what amounts to "fixed expression" and that copyright doesn't cover "ideas" - but please scroll down to pages 31-34 of the PDF file of the decision below and then try to say the following to yourself with a straight face: "Copyright doesn't protect ideas, only the fixed expression of ideas."
This decision is an absolute farce and outrage. But what it is not is an aberration. It is instead an accurate and standard application of what our current monstrous copyright laws have become, and why anyone who cares about free speech, civil rights and basic human freedoms must now support serious copyright reform in order to roll back its scope.
Read and see for yourself just how far copyright goes in placing a stranglehold over ideas here:
http://www.courthousenews.com/2011/07/21/LaChapelle%20Rihanna%20lawsuit%207-21.pdf