But licensing loopholes mean that's not always the case, and while too much alcohol and too many people is a volatile mix at the best of times, on New Year's Eve the risk of trouble is magnified.

Footage captured on CCTV has revealed the vicious beating of nineteen-year-old nightclub patron Nicholas Barsoum. He was dragged to the club's basement by bouncers at Sydney's Ivy nightclub and bashed - the assault eventually ending with a night in hospital.

Two of the three attackers have since been jailed, but the question of what happens when protectors turns predators had reared its ugly head.

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Security guards might be used to dodging punches, but now bouncers are trying to protect themselves from law breakers in their own ranks.

Loopholes mean that potentially thousands of crowd controllers with fake licenses and no proper training are working illegally.

According to Gary Oliver, the board director of the Security Providers Association of Australia they are "untrained, unsupervised and unlicensed. There are no fingerprints on record and there will be no proper checks done on those people."

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The former police officer is blowing the whistle on a security licensing system that is anything but secure.

"There is no security feature to our licenses. We don't even have our date of birth on our license," Oliver said.

"There is nothing special about the card. There is no holograms, no chip."

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What concerns Oliver is that fake licenses are being used to secure professional recognition.

"This is a national issue. We have to trust the people that hold these licenses and Government agencies must ensure that these licenses can be trusted," Oliver said.

And while up to 97 per cent of crowd controllers are working within the law, he says "there's a lot of issues in the industry that we need to address so the community can have faith in that authorised license holder, and that is what this is about."

This reporter is on Twitter at @DamienHansen7