The North's Human Rights Commission has written to the Commissioner of the London Metropolitan Police asking him to publish his report into the murder of Belfast solicitor Pat Finucane in full.
John Stevens, who has been investigating the murder for the last 10 years, is only expected to publish 15 pages of the 3,000-page report on Thursday.
The Human Rights Commission said Mr Stevens had promised to publish as much of the report as he could without compromising national security.
Mr Finucane was shot dead in front of his family in north Belfast in 1989. There have long been allegations that the British Army and the RUC helped the loyalist paramilitaries who carried out the murder.