Disparity of sentence is the principle whereby it is argued that one defendant should receive a less severe sentence based on a comparison with a co-defendant’s sentence. This can occur in one of two circumstances; firstly, where similar cases are sentenced differently, an secondly where different cases receive the same sentence.
Disparity does not form a separate ground of appeal and so will need to form either a part of, or the basis for, an argument that the disputed sentence is manifestly excessive or wrong in principle. Consequently, disparity argument can be mounted when a sentence is and is not manifestly excessive.
Consider whether right-thinking members of the public thought that something had gone wrong with the administration of justice, R v Fawcett and Others 1983 5 Cr App R (S) 158.
The Court of Appeal has sought to reduce the scope of disparity. Consequently, arguments which has previously seemed more likely than not to find sympathy with the court have been rejected.
Does a disparity in sentence mean a reduction?
No. When considering the appeal against the fine imposed on Balfour Beatty, imposed after convictions arising out of the Hatfield rail crash, the Lord Chief Justice said that disparity between the sentences of two defendants was not an automatic reason for reducing a sentence.