A look at the year gone by since Smith and Warner were banned following the ball tampering controversy (4:42)

Mark Taylor, the former Cricket Australia Board director, has admitted that a "grey area" remains about how long the national team was using illegal methods with which to alter the ball's condition prior to the Newlands scandal that resulted in bans for Steven Smith, David Warner and Cameron Bancroft.

Former captain Smith, ex-deputy Warner and the opener Bancroft were all suspended under the CA code of conduct for their actions during the Cape Town Test, but the investigation commissioned by the CA Board and conducted by the then head of integrity Iain Roy was limited in scope to that Test match specifically, with no powers to look more deeply into the matter.

Speaking on the one-year anniversary of the scandal, Taylor has conceded that these terms of reference have left questions lingering even as Smith, Warner and Bancroft have returned to the game and are all in the frame to be part of Australia's tour of England this year, which includes both the World Cup and the Ashes.

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"There was no probe into finding out how long it had been going on for," Taylor told Wide World of Sports. "Was this the first time? There's no doubt this 'ball management' has been going on for a long time, and I dare say every country is either doing it or working out how to do it, but there's a line somewhere between ball management and ball tampering.

"The grey area in all of this is how much of this ball management in the past was tampering and went unnoticed."

Looking at the underlying reasons for the scandal, Taylor said that the Australian team had become preoccupied with reverse swing to the exclusion of all other methods of getting the ball to move and bringing the bowlers into the game.

"One of the reasons I think Australia fell into trouble in South Africa last year is because they got so fixated on reverse swing," Taylor said. "They had three of the finest fast bowlers in world cricket, and 10 overs into a Test in South Africa they're working on how to manage the ball to get it to reverse.

"They got too carried away with reverse swing and forgot about orthodox, normal swing bowling that's been around for 140 years."

Smith, Warner and their Newlands team-mates, including the now captain Tim Paine and the fast bowlers Mitchell Starc, Josh Hazlewood and Pat Cummins can expect plenty of further questions about the scandal from the moment they arrive in England ahead of the World Cup in May.