Ms Mackie, 54, has pleaded not guilty to the murder of Marnie-Lee Cave, 26, who died from strangulation, before her body was thrown off Handcocks Bridge at Mogareeka in October, 2015.

The Crown alleges a jealous Mackie assaulted Ms Cave, before helping her former partner Bernard Webber kill her with a ligature around her neck.

Mr Webber took his own life in the days after Ms Cave’s death, after being questioned by police and providing a DNA swab.

On Friday and Monday the jury heard from detectives overlooking the investigation, and the implementation of an undercover operative posing as an old friend of Mr Webber.

The operative was used in an attempt to obtain a confession of involvement from Mackie.

Detective Sergeant Justin Marks told the court on Friday the covert method was used after “all avenues were investigated”.

He admitted the operative claiming to be in contact with Mr Webber’s spirit was “dangerous territory” as he may be seen by Mackie to be a “fruit loop”.

Det Sgt Marks told the court he took a statement from Mackie after she appeared alongside Mr Webber at Bega Police Station unannounced five days after Ms Cave’s body was found. 

Det Sgt Marks told the court Mackie handed him two phones, one with a number of Facebook messages to Ms Cave in the afternoon of October 13, and told him she was aware Ms Cave had died the same day. 

He said after questioning as to how she knew this, Mackie began to “visibly shake and cry”, before telling him she became aware of Ms Cave’s death following a text message from a friend which she had since deleted.

Crown prosecutor Kate Ratcliffe and Mackie’s defence barrister Peter McGrath will present their closing addresses to the jury on Tuesday.

Justice Megan Latham of the NSW Supreme Court is presiding over the case.