Police allege Connor Manns, 18, visited the dealer with senior club member Alex Bourne, who told the victim he would have 'run through' his house, tied him up and stuck a gun in his mouth if the property hadn't been fitted with CCTV cameras.

Bourne allegedly said he and Manns had been sent by club members in Sydney and they would instead "have a conversation" with the dealer the night of December 7, the ACT Magistrates Court was told.

He allegedly told the man if he was going to peddle drugs, he could only sell them on behalf the Comancheros, and he owed the club $10,000 for previous deals in their territory.

The dealer, fearing for his safety, handed over some drugs and cash before the pair left.

An hour later he was allegedly contacted by Bourne via the encrypted messaging app Wickr and told his bosses needed the full amount.

The pair allegedly arranged to meet at Zambrero restaurant at the Canberra Centre, where the dealer handed over $6000 cash in a brown paper bag before telling Bourne he didn't want any more to do with the bikie gang.

"You have my word, you won't hear from me again," Bourne's alleged to have said.

But the court heard the dealer later received another encrypted message from a user called "Jockyt", who police allege was Manns, which read: "You lied to us."

Manns allegedly demanded $15,000 cash and wrote: "Don't start a war you can't finish.

"If you don't reply you will see us sooner than you think."

Soon after, another message arrived which read: "Tick tock tick tock."

He allegedly contacted Bourne, who asked what the dealer could give them. They arranged a meeting, which the dealer later cancelled.

Bourne was charged with blackmail over the alleged incident following a police investigation and was in custody, the court heard.

Manns pleaded not guilty and prosecutors opposed bail on Tuesday.

Senior Constable Sam Norman, from ACT Policing's anti-bikie Taskforce Nemesis, said Manns was at the very least an associate of the Comancheros and police suspected if he wasn't already a nominee for membership, he could be working towards that goal.

The court heards Manns appeared to have strong links to the club and had been spotted with members at inner city bars such as Mooseheads and Hopscotch.

Senior Constable Norman acknowledged, under cross-examination from Manns' lawyer, that it was not an offence to associate in the ACT, but noted it was illegal to participate in a criminal group.

"The Comancheros is a criminal group and operates solely for that purpose," he said.

He said the dealer experienced "an extreme level of fear" and hadn't previously dealt with the club. He had been given the maximum amount of police security, short of entering witness protection, the court was told.

Manns' Legal Aid lawyer said the defendant's family was mortified by his alleged behaviour and, if bailed, he could leave to live interstate with a relative that afternoon.

But the prosecutor said bail conditions would not mitigate the prosecution's concerns and, if convicted, Manns faced 10 years in prison.

She said Manns' role in the alleged blackmail wasn't minor and noted the Comancheros operated "in a context of fear and standover of witnesses".

Magistrate Margaret Hunter acknowledged the defendant's family was supportive but said the alleged crime was "very serious" and the likelihood he would commit further offences "very strong" given his alleged links to the bikie gang.

"The association with the club is too much in my view," she said.

She refused bail. Manns will return to court late this month.