See Theorem 6 of the GGPR&#x27;12 paper, its on page 26. <a href="https:&#x2F;&#x2F;eprint.iacr.org&#x2F;2012&#x2F;215" rel="nofollow">https:&#x2F;&#x2F;eprint.iacr.org&#x2F;2012&#x2F;215</a> which addresses the rerandomization of the proofs in the prover that result in them being a uniform sample of all acceptable proofs.