Gary Taylor, 24, appeared briefly before magistrate Beth Campbell on Saturday morning.

He appeared in court via video link, dressed in a black hooded sweater with a bright motif on the front and back. He did not apply for bail and was remanded to reappear in court again on July 11.

Two ACT homicide squad detectives sat in the courtroom to observe the brief case proceedings.

The accused showed no emotion when the charge was read, nor did he address the court except to clarify to the magistrate the correct pronunciation of Mansfield Place, the location where the shooting occurred in Phillip.

He had been extradited on Thursday from the remote, tiny town of Baradine, in north-western NSW midway between Dubbo and Narrabri.

Five women, including the mother of the victim, also were in the gallery during the Saturday court hearing.

Mr Walewicz, 48, was shot dead when he answered a knock on the door of his Connorville Gardens unit in June 2021.

Co-accused with Taylor is an 18-year-old man, who cannot be named because he was underage at the time of the killing. He is behind bars on remand after he was arrested last weekend and charged with murder.

Speaking to media about the teenager's arrest, Detective Inspector Mark Steel revealed ACT Policing was investigating the possibility Mr Walewicz was a victim of mistaken identity and not the intended target of the shooting.

Reatile Ncube, 19, and Nicole Williams, 38, were arrested either side of the alleged killer and remanded in custody on charges of accessory to murder.

Williams also faces a related allegation of conspiracy to commit aggravated burglary.

None of the first three to be charged have entered pleas.

Anyone who has any information about this incident is urged to contact Crime Stoppers on 1800 333 000, or via the Crime Stoppers ACT website. Please quote 6821216.

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