She's in the right! (3)
I believe the answer is:
her
'she's' is the definition.
(I've seen this in other clues)
'in the right' is the wordplay.
'in' says the answer is hidden in the clue.
'HER' is hidden in the letters of 'the right'.
(Other definitions for her that I've seen before include "That lady" , "In the Midlands she" , "Pronoun used of ship" , "The female's" , "That lady's" .)