An Army commander allowed his men to violently abuse nine Iraqi detainees in direct breach of the Geneva Convention, a court martial has heard.
Baha Mousa died in custody after being arrested in Basra
Colonel Jorge Mendonca, 42, never questioned the legality of their treatment, it is alleged.
Col Mendonca denies failing to ensure the Iraqi civilians being held in Basra, southern Iraq, in September 2003 were not ill-treated by his soldiers.
Five other soldiers deny abuse charges. A seventh admits inhumane treatment.
The civilian detainees were allegedly hooded, deprived of sleep and beaten - and one of them, Baha Mousa, 26, died in custody.
Asked if he had heard screams coming from the building where the alleged abuse took place, Col Mendonca replied: "I express incredulity at that comment."
Col Mendonca, former commander of the Queen's Lancashire Regiment (QLR), added "his hearing was not what it used to be".
Prosecutor Julian Bevan QC said he accepted Col Mendonca's remark about his hearing, but added: "He is by no means deaf."
Opening his case against Col Mendonca at Bulford Camp in Wiltshire, Mr Bevan said: "Col Mendonca is a distinguished officer, awarded a DSO (Distinguished Service Order) for services in Iraq, an award for gallantry not lightly given.
"Sadly, in this case, his failings in respect of these Iraqi civilians played a part in the way they were treated."
The alleged inhumane treatment, which included detainees holding stress positions such as standing with knees bent and arms outstretched, was known as "conditioning", a practice used to soften up prisoners for tactical questioning.
Mr Bevan said such techniques were commonplace in the QLR despite being outlawed by the Geneva Convention, the Laws of Armed Combat, a 1972 Government inquiry into interrogation in Northern Ireland and the Human Rights Act 1998.
CHARGES IN FULL
Cpl Donald Payne - manslaughter, inhumane treatment of persons, perverting the course of justice
L/Cpl Wayne Crowcroft - inhumane treatment of persons
Pte Darren Fallon - inhumane treatment of persons
Sgt Kelvin Stacey - actual bodily harm, alternatively assault
Warrant Officer Mark Davies - negligently performing a duty
Maj Michael Peebles - negligently performing a duty
Col Jorge Mendonca - negligently performing a duty
Col Mendonca said in interview that a senior officer from the Army Legal Services had indicated that hooding was acceptable, although this is denied by the officer in question.
Col Mendonca said he left conditioning to Major Michael Peebles and Warrant Officer Mark Davies.
Mr Bevan said: "The fact that he delegated this task to Major Peebles did not bring either his responsibility or duties towards the detainees to an end."
Col Mendonca had been taught on a course that hooding, stress positions, noise and sleep deprivation were banned, said Mr Bevan.
Earlier ,the court heard that WO Davies took an active role in the alleged brutality, which he denied in interview, but Mr Bevan said he was a liar.
The trial was adjourned until Monday.