From the highest military officials to the journalists who broke the story, BBC News Online looks at the figures in the Iraq prisoner abuse scandal.
THE MILITARY LEADERSHIP
US Defence Secretary Donald Rumsfeld
Rumsfeld: under attack over charges of abuse by US troops
The hawkish Mr Rumsfeld, one of the chief architects of the Iraq war, faced calls for his resignation when the scandal at the Abu Ghraib prison in Baghdad first broke.
An investigation into abuse at the prison was completed in early March, but even two months later, Mr Rumsfeld said he had still not read the report fully.
He was forced to offer his deepest apologies for what had happened, saying he had not realised the seriousness of the allegations until pictures were leaked to the media.
President George W Bush has thrown his weight behind Mr Rumsfeld, declaring that the nation owed him a "debt of gratitude".
His position is widely held to be secure for the time being. US commentators believe that forcing him from office would be seen as an admission that the administration's Iraq policy is in disarray.
Brigadier General Janis Karpinski
Brigadier General Karpinski found herself in the eye of the storm as the senior US military official in charge of prisons and detention centres across Iraq, including Abu Ghraib.
She led the unit that ran the prison and whose soldiers have been charged with criminal offences.
General Karpinski was suspended in late January as a military investigation into procedures at the prison was carried out.
She has said she believed military commanders were trying to shift the blame onto her and other reservists and away from the intelligence officers still at work in the prison.
Major General Geoffrey Miller
The newly-appointed chief in charge of detention centres across Iraq, Major General Miller previously ran the US prison camp at Guantanamo Bay in Cuba.
General Miller led a 30-strong mission to Iraq in August and September 2003 to focus on ways of sharpening interrogation procedures.
But he has denied the group recommended military police should be involved in interrogation procedures.
Vowing to improve conditions at the jail by cutting numbers, General Miller has said interrogations will continue but pledged all prisoners would be treated in accordance with the Geneva Convention.
Private Lynndie England
Private Lynndie England: the face of the scandal
Pictures of 21-year-old Private Lynndie England appeared in media outlets across the world. They included one of Private England holding a leash tied around the neck of a crumpled prisoner.
In another she smiles at the camera as a cigarette hangs from her lips, pointing a mock gun at the genitals of a naked prisoner.
She has been demoted from the rank of specialist to private first class.
Ms England, who joined the army as a reservist after leaving high school and left for Iraq in February 2003, claims the abuses formed part of tactics approved by her superiors.
Six other members of her unit, the 372nd Military Police unit based in Cresaptown, Maryland, are facing preliminary court-martial proceedings in connection with the alleged abuse.
Specialist Jeremy Sivits
Specialist Sivits, 24, was the first military policeman to appear before a special court martial in Baghdad, where he pleaded
guilty to four counts, including mistreating prisoners and dereliction of duty.
He was jailed for a year, demoted and discharged from service.
Perhaps critically for military officials who are keen to argue that the abuse was the work of a "few bad apples", Spc Sivits says his superiors did not know of the mistreatment of prisoners.
He trained as a truck mechanic and not a prison guard.
Sergeant Javal Davis
Sergeant Davis, 26, has been ordered to stand trial for charges including assaulting detainees, providing a false official statement to investigators, dereliction of duty and conspiracy to maltreat detainees.
Sergeant Ivan "Chip" Frederick
Facing charges: Staff Sergeant Ivan Frederick
Sergeant Frederick is charged with maltreatment of detainees and committing indecent acts, among other accusations.
Before leaving for Iraq in February 2003, 37-year-old Sergeant Frederick was a prison officer at a state jail in Virginia.
In written accounts of conditions at the prison, Sergeant Frederick described his job as preparing inmates for interrogation.
Specialist Charles Graner
A former Pennsylvania prison guard, 35-year-old Specialist Charles Graner worked in the Abu Ghraib prison and is facing charges of maltreatment and indecent acts, as well as adultery and obstruction of justice.
He has said he was following instructions given to him by military intelligence officials.
The other two accused soldiers are Specialist Sabrina Harman and Specialist Megan Ambuhl, also with the 372nd Military Police.
Specialist Joe Darby
Specialist Joe Darby is the military policeman who exposed fellow soldiers taking pictures as they abused the prisoners.
Also a member of the 372nd Military Police on duty in prison, the 24-year-old has been described by friends as having an independent streak and a strong sense of right and wrong.
He has been commended by the military for his actions.
Major General Antonio Taguba
Telling it like it is: Taguba investigated allegations
Major General Taguba authored the initial damning report into the abuses in Abu Ghraib prison.
Known for his calm, straight-talking style, General Taguba's secret 53-page report, leaked to the press, spoke of "numerous incidents of sadistic, blatant and wanton criminal abuses."
General Taguba, whose military career has spanned more than 30 years, said he had found however no evidence of a specific policy directing the abuse.
But he blamed failures of leadership for allowing the situation to develop and told a Senate committee that soldiers faced a lack of training, supervision and discipline.
The report's findings led to Brigadier General Janis Karpinski being suspended.
US Senator John Warner
Chairman of the Senate Armed Services Committee, Senator Warner is the Virginian Republican who heads the body responsible for overseeing the US Defence department.
He called the mistreatment of prisoners appalling and said it represented a totally unacceptable breach of military regulations and conduct.
Senator Warner has backed Bush in supporting Mr Rumsfeld but after grilling the defence secretary he warned repeated viewing of these images could undermine American military operations in Iraq and beyond.
US Senator Carl Levin
Michigan Senator Carl Levin is ranking Democrat on the Senate Armed Services Committee.
He has warned that the abuse would fuel anti-American hatred and said those responsible for authorising such actions must be held accountable.
The CBS 60 Minutes Team
The first pictures and details of what was happening in Abu Ghraib prison were broadcast on the 60 Minutes II programme of US television network CBS at the end of April.
The network delayed broadcasting the revelations for two weeks after an appeal from the Defence Department and the Chairman of the Joint Chiefs of Staff, General Richard Myers.
In the programme 60 Minutes II spoke to Sergeant Ivan Frederick, now facing a court martial.
Mr Hersh is a veteran investigative journalist who first published the leaked Taguba report along with snapshots of prisoners being abused in the New Yorker magazine.
He had said that the pictures make it clear that there was, or had been until recently, a "very systematic problem" in the prison systems in Iraq.
Mr Hersh is famed for his 1969 expose of the My Lai massacre in Vietnam, winning a Pulitzer prize for his work.
He is also the author of several high-profile political biographies including books on Kissinger and John F Kennedy.