Belgian judges said evidence seized by police in raids on the country's Church, in relation to child sex abuse scandals, was invalid.
An appeals court deemed the raids, on the church headquarters in Brussels and at the home of its former top cardinal, disproportionate.
The court then ordered that the material - on hundreds of individual investigations conducted by an internal church commission - be returned, with prosecutors unable to use it, said an AFP report in the Sydney Morning Herald.
The current archbishop, Andre-Joseph Leonard, said after the decision was made public: "It is in everyone's interests that the fundamental rules of law are respected."
He said he was "in no way opposed to a correctly run judicial investigation" and he was "satisfied that clarity has finally been shone on this affair".
The church commission is due to report on Friday on its findings into allegations going back decades, and is expected to shed some light on the depth of the scandal, with about 100 victims having agreed to have their stories told.
The swoops had drawn the anger of the Pope, with church officials indicating police had even opened tombs in the Mechelen cathedral and priests reporting they were denied sustenance over long hours.
Belgian court bins pedophile evidence (Sydney Morning Herald/AFP)
Belgian police raid archbishop's palace