Du Plessis says he is surprised the International Cricket Council did not take action against any player in the wake of the spiteful second Test between Australia and India.

His comments come despite Smith's show of support for his South African counterpart at the time of the mint-gate controversy.

The South African still believes he was harshly treated by the ICC, who found him guilty of ball tampering for a second time in November.

Australia and India's players were not charged by the match referee but ICC chief executive David Richardson did not exercise his power as he did against du Plessis.

The issue escalated when South African team management were accused of manhandling a television reporter at Adelaide Airport, sparking a media frenzy.

Du Plessis believes the poor player behaviour by both sides in Bangalore was worse than shining a ball while chewing a mint, which is prohibited.

"I was [surprised that no one was charged] purely from the reason of what I went through for something I feel was a lot smaller and a lot less ... whatever you want to call it. So yes, surprised with that," du Plessis said after South Africa and New Zealand played out a draw in Dunedin.

"It [the reaction from the ICC] was different. I am surprised by the way it happened. Maybe it's just because I speak on from a personal point of view and I felt that I was treated very harsh but when you see something like that you hope that it would be exactly the same.

"Us and New Zealand are very similar in the way we play. We respect each other on and off the field and we play a similar brand of cricket. We don't see that the way you carry on off the field will have an effect on the outcome. When you play a team like India and Australia that can happen and it's easy to see how that can blow up.

"For me it's been good to be on the other side for a bit and to see how things unfold. It would have been interesting to see how the Australian media would have reacted to me doing that."