"It's an unfair contest at the moment," said De Villiers.
"You almost have to become illegal to be legal. It's hard to go that way because then a different referee could bring out a yellow card for your players.
"At the moment the players and the referee are not on the same page."
De Villiers has called for pre-match meetings to take place between coaches and referees in order for any areas of interpretation to be ironed out before the game begins.
"It's an IRB rule, but I don't know why we can't discuss these things before the game.
"Both coaches should be there the day before a game to speak to the referee.
"These days, there are so many different interpretations of the laws. All you want is clarity from the ref.
"You want to know before hand, you want him to tell you, 'This is how I see it'."
Current IRB rules state that coaches are not allowed to meet with the referee to discuss any matters prior to a match, but de Villiers did succeed in organising such a meeting prior to South Africa's historic win in Dunedin last month after he complained about the All Blacks' scrummaging technique from the previous week's fixture in Wellington.