NSW Police Senior Constable Beau Lamarre-Condon, 28, is in custody after being charged with murdering the couple at Mr Baird's home in Paddington in Sydney's east on February 19.
The bodies of Mr Davies, 29, and Mr Baird, 26, were found inside surfboard bags at the fence line of a rural property in Bungonia near Goulburn, about 200km southwest of Sydney, on Tuesday.
Police allege the murder of Mr Baird, who Lamarre-Condon briefly dated, was premeditated, while Mr Davies was in the wrong place at the wrong time.
Footage has emerged of Lamarre-Condon walking out of a shop with a surfboard bag. (HANDOUT/9NEWS)
"We will be strongly claiming in our case that this murder was premeditated and the second murder occurred because of, unfortunately, Luke's presence at the house," Assistant Commissioner Michael Fitzgerald told Nine News.
Qantas will pay tribute to Mr Davies, a former flight attendant, on its Mardi Gras parade float.
The parade will run through Oxford Street in Darlinghurst, not far from Mr Baird's house in Paddington, on Saturday.
Organiser Brandon Bear said this year's festival would be a time for celebration and mourning.
"Mardi Gras is a multiplicity of things and we come together not just to celebrate, but also to spark conversation to make change and this year, there'll be an element of us coming together to mourn," he told ABC News.
"We're certainly working with the community (to recognise the couple) and we know our partners are working to use their parade float to talk to the lives and the memory of those young men."
NSW police officers will also march in the parade after reaching a compromise with organisers, having previously been uninvited after Lamarre-Condon was charged.
Officers will march out of uniform as part of the agreement.
Lamarre-Condon, who previously marched in the parade, allegedly shot the duo with his police-issued firearm before transporting their bodies to the rural area.
Two days before the killings, he allegedly bought a surfboard cover at a store at Miranda, in Sydney's south, to carry Mr Baird's body.
"Following the incidents and the murders, he went back and bought a further surfboard cover," Mr Fitzgerald said.
Shopping centre CCTV footage published by Nine News showed Lamarre-Condon walking out of a sporting goods store on two separate occasions before and after the alleged murders, carrying a surfboard bag each time.
NSW Police Commissioner Karen Webb confirmed Lamarre-Condon had been served a notice for his dismissal from the force.
Floral tributes have heaped up outside the inner Sydney home where two young men were slain. (Bianca De Marchi/AAP PHOTOS)
Meanwhile, domestic violence rates within the LGBTQI community have been highlighted amid calls for further police training following the alleged murders.
Investigators allege the crimes followed a months-long campaign of "predatory behaviour" by the accused, culminating in the fatal shooting.
Peter Murphy, who took part in the first Mardi Gras march in 1978, said LGBTQI communities were not immune from domestic and family violence.
But many gay and lesbian people were hesitant to report it to police due to historical discrimination displayed by the force, he added.
"Personal relationships, whatever genders are involved, can have an ugly side," Mr Murphy told AAP.
"I don't think there's enough training within the police on these matters and in the next few months I think we'll see a fairly good effort from police, but it can fade off easily.
"If the police response to this is more of a public relations exercise, everyone will be disillusioned."
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