Focarelli appeared by video link in the Adelaide Magistrates Court on Friday charged with trafficking in a controlled drug.
It has been alleged that police found a bottle of drugs in the car the 37-year-old was driving when he flagged down a patrol in January on the night he and his son were shot.
Giovanni Focarelli, 22, died in the attack while Focarelli was hospitalised for several weeks with serious wounds.
On Friday the court was told it was likely a second person would be charged over the drugs.
But Magistrate Robert Harrap said Focarelli was entitled to present his no-case submissions.
Mr Harrap set the matter down for June 1.
Focarelli, who at one stage declared himself the head of the Comancheros in South Australia, also appeared in the Adelaide Magistrates Court on Thursday charged with breaching his bail conditions.
Police alleged he breached the conditions 11 times by having phone conversations with an associate.
A trial on the issue will continue next month with Focarelli remaining in custody in the meantime.