They had it all along

After the weekend's kerfuffle over the SIS "losing" an hour of sound from their illegally-taped interview with Ahmed Zaoui, the police have stepped forward to say that they have a seperate audio recording.

While we can at least be thankful that the police aren't as incompotent as the SIS, it does raise the question of why they sat on the tape for so long. Shouldn't they have declared any evidence held by them to Zaoui's lawyers?