From 35,000 ravers and no arrests on NYE 1999 to five deaths this year - why ...

The biggest party Australia has ever seen was celebrated without an arrest, incident or even a death - and it was all fueled by recreational drugs.

In the days after the 1999 New Year's Eve celebrations in Sydney, police praised the behaviour of tens of thousands of revellers who partied through the night after ingesting the popular rave drug 'ecstasy'.

'The big topic of conversation among officers on the night was how the widespread use of ecstasy has really calmed things down,' a senior Bondi police officer told the Sydney Morning Herald at the time.

Now, almost two decades on, drugs are again on the agenda following a spate of deaths at dance music festivals across New South Wales over the past four months.

Daily Mail Australia asked some of those who have watched the ecstasy scene over the past 20 years what has gone wrong and why so many young people are dying. 

A former boss of the NSW Police Drug Squad noted more ecstasy - also known as MDMA - was being manufactured locally and insisted pill testing was not the way to save lives.

An experienced Sydney paramedic warned drug sniffer dogs were actually part of the problem, scaring dance party revellers into taking too many drugs at once. 

And a NSW politician went several steps further, claiming the government had declared war on young people and fun. 

Scroll down for video 

Nick Bingham, who led the drug squad for five years up to 2014, believed increased local manufacturing and users not knowing what they were taking had contributed to the recent deaths.

'In terms of pills that are marketed as ecstasy, 20 years ago most of those pills would have come from Europe, mainly the Netherlands or Belgium,' Mr Bingham told Daily Mail Australia.

'A significant amount is still coming from Europe, but unlike heroin or cocaine which is still strictly imported from other countries, MDMA is now also being manufactured here so it's far more prevalent and therefore there is more chance of harm.

'While MDMA affects one person in one way in terms of giving them a desired affect, another person can also get the desired affect but it can still kill.' 

Since September last year, five young people have died at dance music festivals in NSW.

But across three festivals on New Year's Eve 1999 more than 35,000 revellers partied late into the night without a single reported arrest, altercation or overdose.

While one officer on the beat had praised revellers, the police hierarchy later said that claims ecstasy use had improved behaviour was 'absolute rubbish'.

However, another former senior officer who was based in Sydney's eastern suburbs during the late 1990s and early 2000s said he remembered New Year's Eve 1999 as a turning point. 

'For years prior it was a complete s***fight each New Year's as were the Christmas Days with the backpackers which were on par with New Year's,' he said. 

'I also remember that after 2000 it quietened down dramatically.' 

Prominent Sydney doctor Professor Gordian Fulde, who in 1999 was head of emergency at St Vincent's Hospital, was quoted at the time saying he too noticed a change in patients that New Year's Eve.

While normally swamped with intoxicated patients or those who suffered injuries in acts of violence, in the early hours of 2000 his emergency department was deserted.  

'There has been a major cultural change where the young of today would rather pop a pill, hug each other and dance until dawn - it has certainly cut down the violence,' Professor Fulde told the Sydney Morning Herald in January 2000.

'People realise there is another way to have fun other than going out and getting smashed on alcohol. For a start, the hangover is nowhere near as bad.' 

Professor Fulde, who is now at Sydney Hospital, told Daily Mail Australia 1999/2000 must have been 'a blip on the radar'.

'I do remember one New Year's Eve that was incredibly quiet, but I don't recall condoning drug use,' he said.

'That just does not fit with my view on drugs, which has been consistent for a long time now.

'It is a health problem and it has got to really be looked at. The whole drugs and pill testing thing is nearly a more important issue than Donald Trump right now.'

'I think it's good we’re looking at it all. Things can change massively - marijuana used to be the world's worst thing but now we know it has medicinal purposes and it's even being legalised in some countries.'

A Sydney paramedic with 20 years' experience dealing with drug overdoses has watched the recent spike it deaths with alarm and warned the use of sniffer dogs at festivals was putting more young lives at risk. 

'Drug dogs add to the problem,' he said. 'Kids will take all their drugs at once rather than risk being caught by a drug dog.

'They will pre-load or double or triple dose rather than spacing it out over the course of the event.

'That leads to them overdosing - they become over-active and in turn they dehydrate, their body overheats and by the time they realise they're in trouble it's too late.