Once on the ground, he sustained repeated beatings inflicting injuries all over his body, Southwark Crown Court heard.
Mr Ahmad, who was suspected of being a terror group leader who had trained and fought jihad - holy war - abroad, was beaten up in his home in Fountain Road, Tooting, by the four Territorial Support Group (TSG) officers, with three continuing the assault in a police van and at Charing Cross police station, said Jonathan Laidlaw QC for the prosecution.
The alleged attack came at 5am on December 2 2003 as
the Metropolitan Police launched Operation Quarrier, raiding four Muslim
The operation came 11 months after Detective Constable Stephen Oake was murdered in Crumpsall, Manchester, by terror suspect Kamel Bourgass.
Police chiefs briefed their officers that Mr Ahmad was to be considered as dangerous as Bourgass and feared their target would resist.
"The reality was quite different," said the barrister, saying he remained entirely submissive.
"Dressed only in his pyjamas and barefooted, Mr Ahmad raised his arms above his head to indicate that he was not going to fight or to present any sort of danger or threat to the police."
Police constables Roderick James-Bowen, 40, Mark Jones, 43, Nigel Cowley, 34, and Detective Constable John Donohue, 37, deny assault.
Press Association Ltd. 2011