The informer was given the number 3838.

She was a defence barrister-turned-police informer who claimed to have helped Victoria Police in at least 386 cases involving notorious figures from Melbourne's underworld.

Her identity has now been revealed as Nicola Gobbo, a criminal lawyer who represented a number of gangland figures while she was simultaneously informing against them to police.

A number of criminals, including murderers and drug kingpins, could launch legal bids for freedom as a result of the arrangement.

The first of them, Faruk Orman, has already walked free after the Court of Appeal found a call Ms Gobbo made to police while she was his lawyer constituted a substantial miscarriage of justice.

Drug kingpin Tony Mokbel was one of Ms Gobbo's high-profile gangland clients. ( ABC News )

Victorian Premier Daniel Andrews has announced a royal commission into the matter, and former homicide squad detective Ron Iddles says up to 15 senior police officers turned a "blind eye" to the consequences of the arrangement.

On June 30, 2015, she wrote a letter to Victoria Police Assistant Commissioner Steve Fontana which can now be published after the lifting of suppression orders on the case in the High Court on Monday.

The court found covertly informing on clients was a "fundamental and appalling breach" of the barrister's obligations.

But in the letter, she described how she was motivated by altruism rather than any personal gain.

The letter sets out in detail her story of why she became an informer and the consequences she faced as a result.

The letter is published in full as it appears in court documents, with minor edits for clarity.

Re: Assistance to Victoria Police I refer to our meetings in 2014 and to the letter I wrote to the then chief commissioner Ken Lay (in October 2014) in which I articulated some of my concerns and fears as well as the impact that the revelation of my informer/human source role in the media has had on my life. I refer to and repeat the content of that letter which I will attach to this one in the event that you have not read it. For the sake of completeness, the response I received from Victoria Police in late 2014 to my letter was nothing but disingenuous and offensive. For the writer to reply by inferring that anyone other than police members were responsible for the leaking of highly sensitive confidential information detailing my role was and is simply absurd. Of course that was prior to the IBAC report being handed down in which His Honour Justice Kellam made a number of findings, specifically that the manner in which Victoria Police handled me, as an informer/human source, was grossly negligent.

The police informer addressed her letter to former assistant commissioner Steve Fontana, pictured here in 2013. ( ABC News )

Given that I was not invited to give evidence at the IBAC hearing and nor has any investigator ever spoken to me or offered any kind of explanation as to how not just the fact of my assistance, but the intricate details as well, have become a matter of public knowledge, I remain in a situation in which I accept that this nightmare is not simply going to go away. Nor am I able to take comfort in knowing that those police members who betrayed me have been identified, disciplined or prosecuted. As I think I mentioned to you (or at least to Detective Inspector Ian Campbell), my handlers were aware of intricate personal information about me and when I contemplate where such information may now be, I am disgusted all over again. As an aside, I consider myself very fortunate that the media appears to have forgotten that when the IBAC inquiry was first announced, their (the Government's) own media release made it clear that the inquiry was not a general one about informers but rather a specific enquiry into the "Lawyer X scandal". Whilst I am grateful that Victoria Police applied for and obtained an injunction preventing publication of the IBAC findings, it is clear that some of the content of His Honour's report has been leaked to the media. I have accepted that I will have to continue to live with the prospect that more details may emerge publicly and, with the assistance of a clinical psychologist and a doctor, I will need to continue to manage the literally paralysing fears and uncertainty as well as heightened danger that impacts upon my existence. To enable you to try to comprehend the level of actual stress and anxiety I have to manage, I learned only this week that the Calabrian crime family (Pat Barbaro, Sam Zirilli and co) have been informed that police were provided with a copy of the Bill of Lading pertaining to the importation of what remains the world's largest ever single seizure of MDMA in 2007; they have been told by a journalist that their Bill of Lading was given to police by an informer and that IBAC was provided with the same document which was the subject of specific comment by His Honour Justice Kellam in his final report. It is an understatement to say that over 12 months after the public revelation of me being an informer/human source for Victoria Police, the confirmation that an extremely dangerous Italian organised crime family has learned this type of detail is nothing short of horrifying. To make any kind of long-term decisions about my future is very difficult because of the continuing problems arising from the original leak to the media of the "Lawyer X scandal". My treating psychologist has said on occasion that were it not for my children, she does not think I would still be alive; such is the level of my depression, anxiety and PTSD. I have struggled to cope with the fact that my reputation has been completely destroyed and my ability to obtain employment within the legal profession or even utilising my four degrees and experience is hopeless. A Google search of my name is quite literally sickening (to me), let alone googling "Lawyer X scandal". I also struggle to deal with the fact that any of this has happened given all the assurances I was given (by police) that my assistance would never be a matter of public knowledge. I have been forced to live day to day with a degree of hyper-vigilance and fear as to what will come out next and what impact it will have on my life. My anxiety and fears are compounded by the fact that but for some contact I maintain with a handful of former clients (now convicted offenders), neither I nor, more importantly, Victoria Police, would be aware of just how dangerous the leaking remains. I have lost faith in assurances I have been given that the IBAC report has not been leaked because it is plainly obvious that the very offenders convicted as a consequence of my assistance are well aware of some of IBAC's findings. In any event, the whole issue of how and by whom any information about my assistance was leaked to the media and became a matter of public knowledge, let alone the leaking of IBAC's findings, remains a matter for your organisation to investigate or resolve. Obviously if I am forced into litigation with respect to Victoria Police's negligence in failing to keep confidential my assistance and failing in its duty to me as an informer, then the question of which members were involved and who is responsible would be a matter for a Supreme Court judge to consider.

I sincerely hope that I do not have to pursue any of this by way of Supreme Court proceedings; the further damage and stress it would cause me aside, the embarrassment and problems it would create for Victoria Police would be significant. It has been conveyed to me that it would assist you if I was able to provide details of a "Top 10" kind of list of operations/investigations in which I played a role. It would be unfair and a failure to appreciate the level of my diligence and commitment if that was the only measure by which you assessed my assistance. For that reason, knowing that there are literally thousands of hours of recorded conversations and debriefings as well as many thousands of documents proving without doubt, the immense assistance I provided over a number of years, I am also including some detail as to how and why I began to provide intelligence to Victoria Police and what my assistance included. As I hope you are aware, I helped because I was motivated by altruism, rather than for any personal gain. My actual assistance to Victoria Police began informally via Purana not long after the taskforce was initially formed in 2004. I met as he then was, Detective Sergeant Stuart Bateson, on a number of occasions starting in early 2004, which of course was at the height of Melbourne's gangland war, and at a time when the refusal to assist police by anyone involved or with any knowledge was frustrating investigators. What led me to do that was my own frustration with the way in which certain criminals (Carl Williams) were seeking to control what suspects and witnesses could and could not do or say to police via solicitors, who were not in my view, acting in the best interests of their clients because of the undue influence and control of "heavies" such as Williams. I provided Bateson with information that was of value to investigators in the months prior to suffering a stroke in late July 2004 and again afterwards. In the lead-up to my illness, I played a pivotal role in convincing [name redacted] to "roll over" on Williams, [name redacted] and others and withstanding undue pressure from the Williams crew (and Tony Mokbel) to try to get him to stay silent. I kept Bateson informed of all of this, including solicitors perverting the course of justice and conspiring with criminals to try to ensure a number of gangland murders would remain unsolved or uncharged. As has been documented in the years that followed [name redacted] deciding to help police, his actions (in becoming a witness for police) created a precedent for others to follow and was the crack in the dam wall of silence that led to a flood. He laid the foundation for the prosecution of numerous murderers and others followed his example.

Convicted drug trafficker Tony Mokbel in disguise in Greece in 2007. ( ABC News )

During 2005 I became aware of high-level drug trafficking, money laundering, witness tampering, firearm offences and a variety of other serious criminal activity by virtue of the contact I had with certain clients and their "crews" and "supporters". I also watched as police either totally failed to investigate much of this offending, or failed in being able to obtain evidence to be able to arrest and charge offenders. By September 2005 certain events and circumstances led to me formally starting work as registered informer 3838 (again as an aside, journalists have used that detail as well as the names of my handlers when informing me of the information police sources have provided to them). My breaking point came when I was threatened by Tony Mokbel to ensure that a first-time offender who was operating pill presses and manufacturing tens of thousands of MDMA pills for him, kept his mouth shut and pleaded guilty after he was arrested by the then MDID. Although Mokbel did not actually say that his underling was being financed and supplied by him, it became obvious to me when I was provided with a remand summary and later a brief of evidence by police. This kind of scenario had happened numerous times in circumstances in which I was dealing with high-level drug syndicates, all of whom had individuals who were the targets of police investigations and many of which were involved, directly or indirectly, with the gangland murders. To try to encompass my actual value, reliability and work for Victoria Police in any summary is immensely difficult because from September 16, 2005, I spoke to my handlers on a daily basis, often seven days a week for a couple of years. Again, the media has informed me that there are approximately 5,500 information reports generated from information I provided to police. There was no topic, criminal, organised crime group or underworld crime that was "off limits" during the many debriefing sessions that occurred or during the years that followed until Overland decided to utilise me as a witness in 2009 when everything fell apart. I didn't appreciate that at the time I made the decision to become a witness for Victoria Police, I had been put in a situation in which every assurance given to me was a lie and more importantly, that the investigators who took my statement were not made aware of the very real problems with respect to my safety and status. As you are no doubt aware, that led to me issuing civil proceedings against Overland after enduring 18 months of severe stress and uncertainty when no-one seemed to be capable of making any decision about what to do with regard to the issue of dealing with my informer role when I was called to give evidence. Those proceedings resolved at a mediation in late 2010 (again as an aside, the evening before that mediation my gynaecological oncologist had diagnosed me with the return of cancerous tissue that required surgery and foremost in my mind then and in the time that followed was my health). For completeness, as I am sure you are aware, those proceedings were public and the writ did not include any reference to my role as an informer. (I do not want there to be any suggestion that I have previously been compensated in any way for my assistance to police.)

Former Victoria Police chief commissioner Simon Overland, pictured in 2011. ( Peter Giafis: ABC News )