Judge Finestein refused Greater Manchester Police permission to extend the period for which a man arrested on suspicion of murder in November 2010 could be detained because the 96 hours for which a suspect can be held had expired four days after the original 2010 arrest.
In the process, an interpretation of the law that has prevailed for 25 years was overturned.
Commenting on the development, Sir Norman Bettison, West Yorkshire Police Chief Constable, said: “The issue of putting people on bail for further questioning when they answer their bail is pretty much a dead duck.”