A jury has been shown footage of former Sydney police officer Beau Lamarre-Condon buying a surfboard bag prior to the alleged murders of Jesse Baird and Luke Davies, which prosecutors allege he planned to use to dispose of Mr Baird's body.

Mr Lamarre-Condon has pleaded not guilty to two counts of murder and one of aggravated break and enter, with a NSW Supreme Court trial in its first week.

The 31-year-old is accused of shooting Mr Baird and his new boyfriend, Luke Davies, with his police pistol at Mr Baird's share house in Paddington, in Sydney's east, in February 2024.

The Crown alleges he formed an obsessive and jealous infatuation with Mr Baird, who had twice broken things off with him and requested no further contact.

Mr Lamarre-Condon's defence counsel has flagged with jurors that self defence will be argued, and that it is his case that Mr Baird and Mr Davies died during two separate struggles in the Brown Street property, both involving his service pistol.

Surfboard bag

During the Crown's opening address, jurors were told Mr Lamarre-Condon was accused of planning Mr Baird's alleged murder in February 2024, including by stopping at a sports store days before to buy a surfboard bag to dispose of his body.

A friend was with Mr Lamarre-Condon at the time, the court was told.

On Thursday, the jury was played CCTV of inside a store on February 17, 2024, showing Mr Lamarre-Condon and the friend looking at surfboard bags.

In the footage, he held up a bag next to the friend.

Crown Prosecutor Brett Hatfield SC previously told the jury he anticipated evidence from the friend that the accused asked him whether he would fit inside the surfboard bag, to which the friend replied "probably not".

Mr Hatfield said it would be the friend's evidence that the accused then said: "I'll grab this one instead, it should be big enough."

The footage played today was among several compilations of CCTV footage being shown, including footage of Mr Lamarre-Condon arriving and leaving Balmain Police Station the previous day, driving his Tesla, and stopping at ATMs.

The jury was also shown footage of Mr Baird and Mr Davies at the Beresford in Surry Hills on the afternoon of February 18, 2024.

Accused allegedly cleaned the scene

The officer in charge of the investigation, Detective Sasha Pinazza, told the court investigators obtained thousands of hours of footage from 200 or more locations, covering the period of February 16 to February 23, 2024.

Prosecutors have told the jury that Mr Lamarre-Condon allegedly murdered Mr Davies to eliminate him as a witness to the alleged murder of Mr Baird.

The Crown said after the alleged shootings, the accused bought a second surfboard bag, in addition to allegedly cleaning the scene and using a hire van to transport the men's bodies, which were ultimately found at a rural area south of Sydney.

The trial, before Justice Natalie Adams, has an estimated duration of three months.