The Commons Public Administration Committee listed a number of errors in Cabinet Secretary Sir Jeremy Heywood's inquiry into former chief whip Andrew Mitchell's "plebgate" row.
- The committee said it was "surprising" that Sir Jeremy had not been aware of a note of a conversation that the No 10 head of security and the Prime Minister's principal private secretary had with the officer concerned shortly after the incident.
- They said it was "equally surprising" that he did not establish whether a reported leak of the police log was actually true.
- Sir Jeremy should have advised David Cameron to refer the matter to the relevant police authorities so they could resolve any "discrepancies and inconsistencies", they added.
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