Andrew Strauss insists there are no "thugs" among England's Test cricketers and confirmed Jonny Bairstow will not face disciplinary action over the headbutt incident at the start of the Ashes tour.
England's 10-wicket defeat in the first Test in Brisbane came as details emerged of Bairstow's apparently playful headbutt on Australia opener Cameron Bancroft in a Perth bar on October 29.
The incident raised the subject of player behaviour again in the wake of all-rounder Ben Stokes being made unavailable for the tour as he waits to discover if he will be charged after a late-night fracas in Bristol in September.
Bancroft's narration of Bairstow incident
That saga took another twist on Monday evening when Stokes was pictured in Heathrow Airport, leading to speculation he was on his way to join the England squad.
And although the England and Wales Cricket Board quickly clarified that Stokes was making a private trip to New Zealand and not joining "the Ashes, England Lions or any other official training camps with the England set-up", the situation will not have eased the frustration of coach Trevor Bayliss at some of his players' "dumb decisions".
ECB director and former England captain Strauss praised the players as "honest, hard-working cricketers" and added: "These guys are not thugs. The guys were out for a couple of drinks, there was no curfew in place [and] they were free to enjoy an evening out.
"Jonny Bairstow mentioned to me that he 'bumped' Cameron Bancroft. It's a greeting he does with his rugby mates and he assured me there was no malice, no intent, no aggression in what he did.
"Although I'm somewhat surprised he would choose to do such a thing, I'm taking him at his word. As such, I don't think it would be appropriate for us to be launching disciplinary proceedings against him."
Bancroft, who marked his debut with an unbeaten second-innings half-century as Australia coasted to victory, described Bairstow's introductory gesture as "weird".
Strauss added: "We have done a lot of work over the last five or six weeks, making sure the players understand their responsibilities and obligations and coming up with a code of conduct for them.
"I think we also need to understand and recognise that sport is moving on. What might have been acceptable in the old days is no longer acceptable, and we as an England cricket team ... need to move along with that.
"I think the players needs to be smarter. That's the reality. They are adults, intelligent adults, and at times they are not using that intelligence in the right way."
Asked on Monday if he thought Stokes's experiences might have prompted the players to be more careful, Bayliss said: "That was what I thought after Bristol as well. They'd be extra dumb and stupid if it didn't.
"That's the disappointing thing - we make dumb decisions. If you put yourself in that situation you are fair game."