It's emerged some witnesses to the inquiry into former Justice Minister Judith Collins wanted details of the investigation suppressed.

Justice Chisholm's referenced the request in his report that's found Ms Collins played no part in efforts to undermine former Serious Fraud Office boss Adam Feeley.

His report says that extended to a request that the full record of the inquiry be suppressed.

Justice Chisholm ruled such a sweeping move would be inconsistent with the Inquiries Act and favoured a more open approach be taken.

However, his draft report and submissions to his inquiry have been withheld.