His comments yesterday follow World Rugby’s admission that South African referee Craig Joubert blundered in awarding Australia their decisive penalty against Scotland last Sunday.
The governing body received fierce criticism for publicly stating that Joubert should have awarded a scrum instead.
Wallabies stand-off Bernard Foley kicked the three points to snatch a 35-34 victory, but the call for accidental offside was incorrect. Joubert will not be involved in this weekend’s semi-finals.
Hansen said: “The referees make mistakes. As long as they take a breath, they will make them, because players do and coaches do.
“So if you can accept that, the best way to avoid that mistake being the game-winning mistake, for want of a better term, is to make sure you are in front by enough for it not to be.
“Quite often, when a mistake is made and it’s right at the end of the game, it’s obvious for everyone to see and we get carried away with it.
“Sometimes they (referees) make mistakes at the beginning of the game that have a massive effect on the result, but no one sees them because they are not caught in the emotion of that last penalty goal or whatever it might have been.
“I’ve always said it is a really tough game to referee at the moment, and we’ve got to find ways of making it simpler for them to get that right. I know you are alluding to Joubert but I don’t think it’s Craig that is the problem but the system.”
Joubert was not allowed to consult the television match official to assess the contentious passage of play.
And reflecting on the use of technology, Hansen added: “When you’ve got technology that sits there and everyone says ‘why didn’t he use it?’ Well, he couldn’t use it, and that’s the problem.
“And World Rugby has to fix that problem.