Paine confronted media in Hobart on Friday to announce that he was resigning from the captaincy, but stressed that he wanted to remain a member of the Test squad.
The 36-year-old read out a short statement but did not answer questions.
“It’s an incredibly difficult decision, but the right one for me, my family and cricket,” he said.
“As a background to my decision, almost four years ago, I was involved in a text exchange with a then colleague.
At the time, the exchange was the subject of a thorough CA (Cricket Australia) integrity survey, during which I was fully involved and openly involved.
“Although apologetic, I deeply regretted this event at the time, and still do today.
“I spoke to my wife and family at the time and am extremely grateful for their forgiveness and support.
“We thought this event was behind us and that I could concentrate entirely on the team, as I have done for the last three or four years.
Source: Cricket Australia
“However, I have recently become aware that this private text exchange will become public.
“Considering, my actions in 2017 do not meet the standard of an Australian cricket captain, or the wider community.
“I deeply regret the pain and sorrow I have caused my wife, my family, and the other party.
“I’m sorry for any damage this does to the reputation of our sport.”
Paine was elevated to the captaincy in March 2018 following the explosive aftermath of the ball troop scandal in South Africa.
Fast bowler Pat Cummins is Australia’s vice-captain and was advised to assume the role after Paine retired.
“Tim felt it was in the best interests of his family and Australian cricket to make this decision to retire as captain,” said CA president Richard Freudenstein.
“The board has accepted Tim’s resignation and will now work through a process with the national election panel to identify and appoint a new captain.
“Although the board acknowledges that an investigation freed Tim from any violation of the code of conduct on this issue a few years ago, we respect his decision.
“CA does not tolerate this type of language or behavior.
“Despite the mistake he has made, Tim has been an exceptional leader since his appointment and the board thanks him for his outstanding service.”
Cricket Tasmania issued a statement claiming that the charges raised against Paine were only raised when the employee was charged with theft.
CT President Andrew Gaggin said no complaints were made until mid-2018 after the message exchanges in November 2017.
“As soon as Cricket Tasmania was aware, it conducted an investigation that determined that the interaction was consensual, private, took place only once, was between mature adults and did not recur,” Mr Gaggin said.
Paine played 35 Tests for Australia, taking 150 catches behind the stumps and has a batting average of 32.63.
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