Claremont murders cop did not use gloves

A forensic supervisor has revealed the collection of a vital exhibit in the Claremont serial killings case was not filmed and also admitted he touched a separate piece of evidence without wearing gloves.

Confessed rapist Bradley Robert Edwards, 51, is on trial in the Western Australia Supreme Court accused of murdering secretary Sarah Spiers, 18, childcare worker Jane Rimmer, 23, and solicitor Ciara Glennon, 27, in 1996 and 1997.

Prosecutors claim Edwards' DNA was found under Ms Glennon's fingernails, plus fibres found on Ms Glennon and Ms Rimmer matched Edwards' Telstra-issued work clothes and a car he had access to at the time.

But the collection of a crucial hair sample from Ms Glennon - labelled RH17 - was not documented in the forensic video.

"I am aware of that," former sergeant Robert Hemelaar said during his third day of testimony on Friday.

Camera operator Michael Teraci previously testified there was a 15-minute period that was not recorded, probably because he was changing the battery.

Mr Hemelaar, who was present for the recovery of the bodies of Ms Rimmer in Wellard in 1996 and Ms Glennon in Eglinton in 1997, added it was not common practice at the time for every exhibit to be filmed.

Defence counsel Paul Yovich noted in the crime scene video for Ms Rimmer there was an instance where lead forensic pathologist Karin Margolius put some vegetation inside a bag and Mr Hemelaar poked it with his bare hands.

Mr Hemelaar agreed he would not do that now.

He said police practices had since developed to become more stringent.

At the time, police wore gloves when touching a body, but not necessarily if they were just in attendance at a crime scene, and boot covers were introduced in 1997 but were not mandatory, the court heard.

Mr Hemelaar said gloves were actually worn for "personal protection" at the time so officers would not get "super dirty (and) smelly".

He also said DNA "was not a factor" in those days.

While DNA forms a significant part of the prosecution's case against Edwards, the defence has repeatedly attempted to poke holes in the argument by suggesting contamination is an issue.

The videos of the body recoveries were previously played in court but are among images and footage that Justice Stephen Hall deemed too distressing to show to the public gallery.

A large barrier has been erected behind the bar table to prevent the public from seeing such graphic vision.

Ms Rimmer and Ms Glennon were found dumped in bushland in similar positions under foliage.

Ms Spiers' body has never been found.

The state's so-called 'trial of the century' has been adjourned until Monday.