Some Australian swimmers abused prescription drugs and bullied teammates in a toxic culture which went unchecked at the London Olympics, an independent review has found.
The report found the London pool campaign unravelled as a lack of leadership, collapsing morale and animosity between swimmers cruelled performances.
Australian swimming's worst Olympics in two decades was undermined by a lack of moral authority and discipline which manifested in a "schoolyard clamour for attention and influence".
The independent review, commission by Swimming Australia in the wake of the London flop, cited incidents of "getting drunk, misuse of prescription drugs, breaching curfews, deceit, bullying".
"Situations were left to bleed," the report said.
The festering and lack of leadership caused swimmers to feel alone and without support.
"Swimmers described these Games as the lonely Olympics and the individual Olympics," the report said.
Morale fell as the publicly anticipated flow of gold medals failed to eventuate, with pressure mounting and no plan enacted to cope with the situation.
"As the first week unravelled, the swimmers felt undefended, alone, alienated ... they felt confused and unsupported by their own team in some cases and not supported well enough by SAL (Swimming Australia Limited), even from the stands."
The report found the "glorification of a few was seen somewhere between embarrassing and irritating to other team members".
"One person said he felt that it was not really about whether you swam your heart out, it was about whether you could sell your heart out," it said.
"Some athletes let their emotion play out as bravado, withdrawal, disinterest and sulking.
"This tension was not nipped in the bud ... indeed it was heightened with scuttlebutt and assumptions and diagnoses of doom from the media and the pool deck."
The report said some older athletes saw the storm brewing and attempted to intervene, but their attempts were seen as being negative and criticising.
"Some individual incidents of unkindness, peer intimidation, hazing and just bad form as a team member that were escalated to personal coaches were not addressed and had no further consequence."
Head coach Leigh Nugent and some support staff didn't hear about most of the incidents until they returned to Australia.
"Athletes felt disconnected from the head coach, and their sense of duty was localised," it said.
"Things were managed quietly rather than brought to a head and several examples of coaches passing over the responsibility for hard conversations were given."
Australian swimmers won just one gold, six silver and three bronze medals at the London Olympics, the lowest return at the pool since the 1992 Barcelona Games.
The swim team entered London amid claims of schoolboy pranks at a lead-in camp, with allegations that senior members of the men's 4x100m freestyle relay team devised an initiation ritual involving taking the prescription sleeping pill Stillnox on a bonding night.
The review recommended creating an ethical framework for Australian swimming - a position of what the sport, governing body and athletes won't stand for, and also stated goals and values.
The review also said internal codes of conduct for swimmers, coaches and staff be updated with reference to team rules at camps and events.
There also should be clear processes designed for managing issues around standards and expectations.
"There is a dire need to develop and enable leadership throughout swimming," said the report, recommending multi-faceted leadership development programs for athletes.
And the head coach should also undergo an intensive "coach-the-coach" leadership program lasting at least three months.