Descendants bikie member Christopher Platt has pleaded guilty to aggravated affray and criminal association

The instigator of the bikie gang brawl that allegedly involved more than a dozen people over a Facebook car sale has pleaded guilty in court.

The instigator of an “ambush-style” attack at an Adelaide car yard will be sentenced next month for the car yard brawl that led to the arrest of 12 members of a bikie gang.

Christopher Platt, of Paralowie, pleaded guilty by video link in Adelaide Magistrates Court on Monday to aggravated affray and criminal association.

The 11 other Descendants bikies arrested over the brawl at the car yard on Main North Rd, Blair Athol on June 2 also appeared in court on Monday.

They did not enter any pleas and were all given a pre trial conference date of February 16.

Platt’s charges were adjourned to December for sentencing.

The Blair Athol car yard where a brawl involving at least 11 members of the Descendants bikie gang occurred on Tuesday June 2. Picture: Gabriel Polychronis

The court previously heard the fight, in which the bikies allegedly attacked two victims, was over a car sale from Facebook Marketplace.

The court heard the first victim bought the vehicle from Platt in January and was told there was no finance owing on the car.

The victim later decided to sell the car and took it to a friend who owned the car yard, where it was discovered there was finance owing on the car and its odometer may have been tampered with.

The court heard the victim asked Platt to meet him at the car yard and once he arrived asked that he pay the outstanding money or fix the car.

Platt became enraged about the situation and offered to buy back the car for $3000, when the victim had paid $10,000.

“(Platt) started yelling, saying ‘You f***ing c***, what are you going to do? Are you going to call the cops?’,” prosecutors previously told the court.

“Mr Platt said words to the effect of ‘If you involve the cops or anyone I will shoot you’.

“(Platt) has then punched the victim to the left eye. Immediately following this, the victim states … approximately 10 men ran towards the yard and started punching; some were armed with various weapons, including a pole, hammer and knife.”

The court previously heard a second victim, who was in the car yard’s office when the men arrived, was also attacked in the “ambush-style” assault.

“They essentially surrounded the car yard, they all approached in an ambush-style situation and took part in the assault against the victim and the workers who were present in the yard,” prosecutors said.

It is against state law for three or more bikie gang members to be together in public.

The Descendants gang is one of the 10 Declared Criminal Organisations.