'What in the hell is going on?'

Darren Lehmann's highly scrutinised use of a two-way radio as Australia's ball-tampering scandal unfolded was a desperate act to learn what his players were up to on the field, according to Cricket Australia's CEO James Sutherland.

The Australian coach found himself heavily embroiled in the controversy when SuperSport cameras showed him on the walkie-talkie to Peter Handscomb, the 12th man, who then ran onto the field to speak with Cameron Bancroft.

David Warner and Steve Smith have been banned for 12 months for their roles in the tampering scandal, while Bancroft has been banned for nine months.

Handscomb spoke briefly to Bancroft before leaving the field, and a short time later, while the on-field umpires conferred with each other, Bancroft was seen removing what has since been identified as sandpaper from his pocket and tucking it down his trousers.

As the realisation of what was occurring spread, the images of a stony-faced Lehmann on the radio were repeatedly broadcast along with footage of Bancroft's transgressions, leading many to leap to the conclusion the Australian coach must have been involved.

A popular theory was that Lehmann had sent Handscomb to inform Bancroft he'd been spotted and to dispose of the evidence.

Such a series of events implicated the bulk of the Australian playing and coaching staff, and the theory was one that social media commentary, led by several former international players, was happy to run with as calls for the coach's head grew ever louder.

Sutherland moved to quash that today, saying CA's Head of Integrity Iain Roy was satisfied that Lehmann knew nothing of the ball-tampering plan prior to its exposure.

"(Lehmann) sent a message to say 'What in the hell is going on?' – he didn't use 'hell', he used another word," Sutherland told reporters in Johannesburg today.

"That was found to be, through Iain's investigation, found to be the fact, and I want to make that point very clearly that Darren made those comments and Iain was certainly satisfied that Darren wasn't involved and didn't know anything of the plan."

Roy found vice-captain Warner to be the chief architect of the deceit, demonstrating to Bancroft how to use the sandpaper to rough up the ball before sending him out on the field after lunch on the third day at Newlands.

Warner was found to have been responsible for the "development of a plan to attempt to artificially alter the condition of the ball", and "instruction to a junior player to carry out a plan".

The former vice-captain was also charged with providing advice to a junior player on how to tamper with the ball "including demonstrating how it could be done".

Warner also misled the Newlands match officials by concealing his knowledge of and involvement in the plan and did not voluntarily report his involvement.

Smith's ban was based on him knowing of the plan but failing to take steps to prevent it.

Further, CA's investigation found that it was Smith who directed "that evidence of attempted tampering be concealed on the field of play". In other words, Smith told Bancroft to hide the sandpaper in his trousers, not on instruction from Lehmann.

Smith was also found to have "misled match officials and others regarding Bancroft's attempts to artificially alter the condition of the ball" and "misleading public comments regarding the nature, extent and participants of the plan".

Bancroft, the most junior member of the playing XI in Cape Town, was banned for his role in being party to the plan to tamper with the ball, carrying out Warner's instructions, following Smith's direction to conceal the evidence and his own lies to mislead match officials and the public.

Qantas tour of South Africa

South Africa squad: Faf du Plessis (c), Hashim Amla, Temba Bavuma, Theunis de Bruyn, Dean Elgar, Heinrich Klaasen, Quinton de Kock, Keshav Maharaj, Aiden Markram, Morne Morkel, Chris Morris, Wiaan Mulder, Lungi Ngidi, Duanne Olivier, Vernon Philander, Kagiso Rabada, AB de Villiers.

Australia squad: Joe Burns, Pat Cummins, Peter Handscomb, Josh Hazlewood, Jon Holland, Usman Khawaja, Nathan Lyon, Mitchell Marsh, Shaun Marsh, Glenn Maxwell, Tim Paine, Matt Renshaw, Jhye Richardson, Chadd Sayers, Mitchell Starc.

Warm-up match: Australia beat South Africa A by five wickets. Report, highlights

First Test Australia won by 118 runs. Scorecard

Second Test South Africa won by six wickets. Scorecard

Third Test South Africa won by 322 runs. Scorecard

Fourth Test Wanderers, Johannesburg, March 30-April 3. Live coverage