Richard Roll was the sixth witness to be called for the claimants during the Horizon trial. He was cross-examined on 13 March 2019. You can read his witness statement on scribd (WS1 here and WS2 here) or embedded below.
Horizon trial: Richard Roll witness statement 1 by Nick Wallis on Scribd
Horizon trial: Richard Roll witness statement 1 by Nick Wallis on Scribd