Victoria Police says it has completed a rollout of 9,000 body-worn cameras.

The force says the devices have been deployed to all frontline officers ranked sergeant and below, as well as protective services officers and other specialist units.

The cameras can be switched on by police, at their discretion, during the course of their duties such as when they exercise powers or collect evidence.

The $42.6 million operation has been underway since it was funded in the 2016 state budget - part of a $227 million police technology boost that also included over 9,000 iPhones and iPad Minis.

VicPol selected Axon Body 2 devices, made by the same manufacturer as cameras worn by the Queensland Police Service, Northern Territory Police and ACT Policing.

Professional standards command assistant commissioner Russel Barrett said they are already helping.

“Throughout the past several months, many police officers have noted an increase in early guilty pleas which leads to faster and easier outcomes for victims and witnesses,” he said.

There have been significant concerns over the oversight and accountability of the scheme.

Last month, reports claimed  officers can edit their footage before court cases, which Victoria Police denies.

“Under no circumstances can police edit original footage or delete it while it’s still going through the complaints or legal system,” it tweeted last month.

The devices also made headlines after a police officer wore a “EAD [eat a dick] hippy” sticker on his device while policing an anti-mining protest.