Two police officers suspended on full pay for seven years have been told to resign after an internal inquiry.
The Met says the case is its longest-running misconduct inquiry
John Redgrave and Michael Charman were at the centre of what police believe is the longest-running police misconduct case in "modern history".
Charges under the Official Secrets Act and of perverting the course of justice were thrown out by the courts in 1999.
But a delayed internal inquiry found them guilty of "discreditable conduct" on Thursday.
The Metropolitan Police Federation, which represented the officers, estimates the case has cost hundreds of thousands of pounds.
Det Insp Redgrave and Det Con Charman were alleged to have tried to destroy documents in July 1998.
The documents related to a case in which they were being investigated.
Both were suspended in February 1997, then arrested and charged in 1998.
A year later they were cleared of criminal offences by the courts and an internal disciplinary process began.
But police say it was repeatedly delayed by legal arguments, the absence of one of the discipline panel and applications both for a judicial review and to the Court of Appeal.
On Thursday Metropolitan Police Federation chairman Glen Smyth said: "This has been nothing short of a personal disaster for the officers and a financial disaster for the taxpayer."
He added: "They have simply achieved what the officers offered them at least two years ago, which was to resign."
Commander Phillip Hagon, of the Metropolitan Police's directorate of professional standards, said the case did not reflect the usual length of misconduct cases.
But he said the length of some internal discipline cases remained "a matter of concern".
"It is extremely frustrating for all concerned that this matter has taken so long to reach a final resolution."
He added: "It is right that in those cases alleging serious dishonesty that officers are prevented from slipping into retirement without any hearing to determine their guilt or innocence."