Sic Semper Tyrannis - Revenge for the South

[Peter Taltavul]

I have always wondered whether JWB - as an actor - had planned on shouting a statement when shooting the President, or if it was spontaneous.

Are there differing accounts as to what Booth shouted and when? Didn't Maj. Rathbone say that Booth has shouted something in the Presidential box?

I seem to recall reading from different sources that "Sic Sepmer Tyrannis" was the cry and also "Revenge for the South." Is there a consensus among historians as to whether both of those phrases were used? If so were both delivered from the stage during the escape?