The 18th birthday party of Chevalier graduate Edward Rabbidge turned into a nightmare of violence for Robert and Marion Rabbidge.

Nine gatecrashers were ejected at 10.30pm on January 26 2008 only to return in a mob of 60 youths brandishing clubs, tree branches, cricket bats and a pool cue at 11.30pm.

Bowral Police Station was closed as local police had all hands on deck to control the riot. Six people were seriously assaulted during the brawl that lasted 20 minutes before police brought it under control.

One man was struck unconscious, Marion Rabbidge was hit with a bottle and punched, and several other people were also attacked with glass bottles at the party turned brawl in Soma Avenue Bowral.

Courts in Moss Vale and Sydney recently handed down sentences but none of the offenders were jailed.

During a lengthy investigation Bowral detectives named 36 people as uninvited party guests and 20 were prosecuted for offences ranging from robbery, assault and affray.

Despite the pre-mediated nature of the group attack and the viscousness unleashed on the party guests the harshest penalties handed out was a six month suspended sentence.

A teenage girl who hit Marion Rabbidge, smashing her glasses, received 300 hours community service while a Mittagong man, who attacked three people, was put on a two-year good behaviour bond. None of the invited guest was charged with any offences.

During the brawl, which escalated from a standoff between the two groups in the driveway, one man was hit and pushed into a one metre high ditch before having his head stomped on, police said.

The court heard the mob were yelling, "we are Sparta", "revenge" and "f**k you Chev" as they stormed towards Soma Avenue after gathering at the Bowral Swimming Pool carpark.

The ugly incident had shades of the 2005 Cronulla race riots with three members of the mob draped in Australian flags and several young men taking their shirts off to brawl.

One offender later told police he had a vendetta against Chevalier students. "They are rich kids who think they are better than us", he said, according to police.

The gatecrashers believed the small group, who had been earlier ejected, had been "rolled" and several people on their way to the party were warned by the group of their intentions to seek revenge on the party guests.

Any of the guests that went to the aid of a guest in trouble were set upon by several of the gatecrashers. During the mayhem one man picked up a large rock before Robert Rabbidge convinced him to put it down. Tim Hill was "king hit" when he went to protect Marion Rabbidge after she was attacked.

The garage at the Soma Avenue address acted as a makeshift field hospital with victims rushed there to escape the violent brawl.

The first triple 000 call was shortly after 11.30pm and 13 calls were made until 11.53pm. Inspector Hansen said police were called at 11.39pm and officers were on the scene within minutes.

More than 10 police from Bowral, Moss Vale and Marulan attended the riot with units from Campbelltown called off once the situation was under control, Inspector Hansen said.

Police arrested 17 people in February with the help of Nowra, Illawarra and Wollongong commands.

Goulburn command crime manager Inspector Ward Hansen said the Rabbidges were satisfied with the police investigation. Inspector Ward said the police response to the riot was swift.

In a related incident, three men were robbed of their liquor on their way to the party in an apparent retaliation for the first group of gatecrashers being ejected.

One man was punched in the face and two had their bags with pre-mixed drinks stolen in the Bowral Swimming Pool carpark. One of the attackers triumphantly told his mate "let's get pissed boys" after taking the liquor, police alleged.

20 rioters prosecuted, no jail given

MOST of the Australia Day riot offenders, many of them teenagers who appeared in children's court, were convicted of affray but avoided jail time. Many were given good behaviour bonds ranging from six months to two years and most escaped with 20 hours community service.

The maximum sentence for affray is 10 years jail but in local courts the maximum sentence is only two years.

For some of the gatecrashers it wasn't their first offence and facts tendered by police indicated the large group was intent on violence when they approached the party after the first group was ejected 60 minutes earlier.

The director of police prosecution dropped all charges for riot, which carries a maximum 15-year jail sentence. Goulburn crime manager Inspector Ward Hansen said it wasn't in the interest of justice to pursue these charges.

Inspector Hansen said it was a labour intense investigation with more than 90 victim and witness statements taken.

While Inspector Hansen would not comment on the sentences handed out but the light sentences seem little reward for the hard work of Bowral and Goulburn detectives. The chaos of the riot made it hard for the DPP to pinpoint exactly who did what to whom but many of the gatecrashers and party guest knew each other from sporting teams.

Two youths were sentenced to two years jail this week for a rampage through a high profile Sydney school where no one was attacked. In comparison a 17-year-old Mittagong man during the Australia day riot, who knocked his victim unconscious with a pool cue and then continued to hit and kick him while he lay helpless, was given a six month suspended sentence and put on a six month control order.

The victim of the pool cue attack, Ben Nickell, had his jaw and eye socket broken requiring plates inserted in his face. He still suffers tingling sensations in his face and cannot move his upper lip and face properly.

The court heard the pool cue snapped in half after Mr Nickell was hit. He then went into an epileptic fit after six men took him into the garage of the Soma Avenue house.