Police email reveals anonymous witnesses

Victoria Police mistakenly revealed to more than 150 people the true identities of secret police who handled high-risk police informers including Nicola Gobbo.

A weekly email update on the royal commission into police use of informers mistakenly left all recipient addresses visible, revealing the real names of officers whose identities are protected for safety reasons.

The force confirmed on Friday that 104 serving and 55 veteran officers, who have been or are expected to be called as witnesses, received the email on Tuesday.

Among them were Source Development Unit handlers who were responsible for managing informers including Ms Gobbo, the lawyer-turned-informer known as Lawyer X.

The identities of those officers weren't widely known within Victoria Police when they belonged to the now-defunct unit and were meant to remain secret.

The inquiry has restricted reporting of any information that might identify them, given them pseudonyms and required that evidence be given over the phone from a remote location.

"Whilst the error is regrettable, and we apologise unreservedly to all affected, we note that every recipient is a veteran or serving police officer, who is well aware of their obligations to protect the security of information," a police spokesman said on Friday.

The email was recalled when the error was noticed and police have contacted or attempted to reach all recipients, the spokesman said.

Commission hearings are due to continue next week.