Allegations made by members of the public had led to the officers being arrested in dawn raids in March last year and suspended pending an investigation by the Police Complaints Authority.
The inquiry, called Operation Gunter, was handled by the West Midlands Police complaints and discipline department, under the supervision of the PCA, and led to seven reports being passed to the CPS.
But the CPS said last night that the evidence in the reports was insufficient to give a realistic chance of a successful prosecution.
The decision follows complaints earlier this week by Edward Crew, the West Midlands Chief Constable, who said in an interview with The Independent that he had corrupt officers working for him but he was unable to sack them.
"There are a very small number of officers in this force, and in the police service nationally, who I suspect of having been involved in serious breaches in the criminal law, where it's not possible to obtain evidence to prove beyond reasonable doubt they were involved in that behaviour," he said.
Jack Straw, the Home Secretary, is now examining ways of improving the scrutiny and punishment of dishonest police officers.
Also this week, the West Midlands force became the second force to set up a confidential internal telephone hotline for staff to pass on information about suspected corrupt officers. West Midlands Police sources said yesterday that the suspended drugs squad officers could still faces serious disciplinary measures.
The PCA said that it was still supervising two more cases relating to allegations about the drugs squad.Reuse content