Third person charged over mistaken identity murder of 40-year-old Joshua Macdonald in Western Sydney

A third person has been charged over the shooting death of a man in Western Sydney .

The 21-year-old man was arrested in Pemulwuy about 6am on Wednesday as investigations continue into the death of 40-year-old Joshua Macdonald .

Macdonald was allegedly shot outside a home on Bruce St in Merrylands West about 3.15pm on September 2, in what police believe was a case of mistaken identity.

CCTV footage from nearby shows a car driving up to and stopping in front of the home before several shots were fired through the rear window.

Police allege the 21-year-old drove the gunman before and after the shooting.

He is also accused of driving people involved in the alleged plot to destroy vehicles used in connection with the shooting.

The man was charged with murder, participating in a criminal group contributing criminal activity and failing to comply with digital evidence access order direction.

His charges follow those laid against 18-year-old Jimmy Schulz and 28-year-old Ashleigh Ann Seeney .

Schulz was arrested at West Hoxton on September 11 after evidence recovered during investigations allegedly implicated him in the shooting.

The alleged drone operator has been charged with murder and remains before the courts .

Seeney, a PE teacher at Airds High School who has since been stood down, was first arrested at a Wollongong unit on Friday.

Police allege she conducted surveillance for those involved in the shooting and helped them escape afterwards.

She was initially charged with being an accessory after the fact to murder, participating in a criminal group and failing to comply with a digital evidence access order, and was granted bail.

However, Seeney was arrested again on Tuesday and charged with three further offences, including conspiracy to murder, participating in a criminal group and failing as an owner to disclose the identity of a driver or passenger.