The results of a third post-mortem examination into the death of Ian Tomlinson are being withheld from the coroner, it was reported on Wednesday.
The examination was carried out on behalf of the police officer who assaulted Mr Tomlinson shortly before he collapsed and died at the G20 protests.
The Crown Prosecution Service, the Independent Police Complaints Commission and the coroner have not seen the report because it is being withheld by the officer's lawyers, citing legal privilege.
City of London coroner Paul Matthews is understood to be seeking a copy.
Mr Matthews has been criticised for using pathologist Freddy Patel to conduct the first post-mortem on Mr Tomlinson.
Dr Patel concluded Mr Tomlinson died of natural causes, but subsequent examinations found that he had died of internal bleeding.
Last week Dr Patel was suspended by the General Medical Council after findings of misconduct or deficient professional performance relating to three earlier post-mortems.
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