But the vast majority of prosecutions don’t make the headlines - in fact, they don’t even make it to trial. It would seem the words of Lord Chief Justice Hewart in 1924 - “justice should not only be done, but should manifestly and undoubtedly be seen to be done” - are no longer true. The massive number of prosecutions would result in the whole system collapsing if even half went to trial, which means there is enormous pressure to do deals beforehand. In most cases, it is in the backrooms rather than open court where the cards of justice are dealt. The raw facts are that for every contested criminal trial in the County and Supreme courts, more than seven are settled with a guilty plea across all courts. According to the Office Of Public Prosecutions, nearly 80 per cent of their cases end with a guilty plea. Put it another way: Every day in court nearly 100 people admit their guilt and waive their rights to fight the charges, while less than two push on to trial in a superior court. The justice process is a giant sausage factory and, as with sausages, few people really want to know what goes into the final product. Or perhaps it is more like the sewer system: While we know where it starts and where it finishes, we are happy to allow the bit in the middle to be conducted underground.

In a meticulously researched new book, Plea Negotiations: Pragmatic Justice in an Imperfect World, by Dr Asher Flynn and Professor Arie Freiberg (for brevity we will call them "the AFs"), we are taken inside the process that keeps the system working. Supreme Court judges on the march. Credit:Michele Mossop The good professor is an expert on such matters and has been the Victorian Sentencing Advisory Council's chairman since 2004 - a position that has put him at odds with many who advocate castration for jaywalking - while Dr Flynn is a criminologist based at Monash University. So why do people plead guilty? Largely because they did it. But why not roll the dice? Because the prosecution offers sweeteners, some that are obvious, others not so. For prosecutors there is the certainty of a win, the shielding of witnesses and victims from the bruises of testifying, reducing the backlog of cases and a chance to have a snappy lunch before going back to the office.

For defence lawyers, it reduces clients’ ultimate sentences, brings certainty to the outcome and gives them a chance for a snappy lunch on the way back to the office. The two AFs found there are 14 separate types of plea negotiations that result in the accused admitting a form of guilt. The truth is the facts, the charges and the level of contrition can be manipulated to keep the matter away from an adversarial hearing, which means the jury trial is now the option of last resort. Professor Arie Freiberg. Credit:Michael Clayton-Jones As one defence lawyer puts it in the book: ‘‘Well my preferred terminology’s horse trading. I’m serious ... that’s what it is.’’ After looking at 50 plea negotiations between 2013 and 2017, the AFs found the popular deals revolve around withdrawing the more serious charge if the offender pleads to a lesser one, rolling up a number of charges into one general offence (50 per cent of all charges are dropped) and ‘‘fact bargaining’’, when both sides agree to a statement of events to put before the court.

The defence pushes for a version to make their client look more like Mahatma Gandhi than Mick Gatto, while the prosecution want something that gets the case done and dusted. The book looks at one case where ‘‘the accused was charged with armed robbery on the basis that he was armed with both an imitation firearm and a knife. The defence offered to plead guilty to armed robbery if the reference to the knife was removed from the summary of facts. This was agreed to by the prosecution.’’ So the facts were altered to get the desired result. Other deals include dropping further investigations, organising bail, promising not to charge associates with related offences, witness protection in exchange for information and other inducements. When the underworld hitman known as "The Runner" agreed to plead guilty and give evidence against drug dealer and killer Carl Williams, he was asked what he wanted in return. He responded he had a hankering for a vanilla slice (he also received protection and a massive sentence discount, which means in judicial terms he had his cake and ate it too). A vanilla slice: Crooks love 'em. Credit:Anna Warr Purana detectives get their man: Carl Williams' arrest. Credit:Angela Wylie

Plea deals proved to be a massive weapon during the Underbelly War, resulting in Purana smashing the underworld code of silence, laying charges over 17 killings and preventing six planned homicides. The greatest incentive to plead guilty is the sentence discount, usually around 30 per cent for saving the cost of a trial and the witnesses the trauma of cross-examination. There appears to be a presumption that admitting guilt comes with a measure of remorse, when the decision is more often based on self-interest than self-awareness. In some cases the offender can double or triple-dip - getting a discount for the guilty plea, a second from the watered-down version of facts and a third from dumping the most severe charges. The AFs found the recent hairy-chested trend of governments introducing mandatory sentences is encouraging offenders to limbo dance under that rigid new bar. ‘‘Evidence from the interviews conducted for the current study also found that in the face of mandatory sentences, defendants were tempted, or pressured, to plead guilty to a lesser charge that did not carry a mandatory sentence.’’

The authors’ conclusion is that plea negotiations are conducted in good faith and are vital to the justice process: ‘‘This is not a lawless system, but nor is it perfect.’’ The pressure to avoid trials can leave some of those involved bewildered and disillusioned. Take the case of Jason Paul Coomber - a man who back on April 15, 2012, lost control of his car and smashed into a tree at Arthurs Creek, killing his passenger, Rhiannon Joy McMahon, 24, the mother of a two-year-old girl. Coomber was driving an unroadworthy car, was high on a cocktail of methamphetamines, ice and GHB, and hadn’t slept for two days. He was charged with culpable driving, which has a maximum sentence of 20 years. Despite having a filthy record, pretending he didn’t know his dying passenger and blaming everyone at the initial hearings - including good samaritans at the scene and emergency workers at the hospital - he was allowed to plead guilty to the much lesser charge of dangerous driving causing death, which carried a maximum of five years. Far from showing remorse, his legal team argued Coomber suffered from the sleeping disorder narcolepsy - deflecting the fact that he had enough drugs in him to drop a bison. He was sentenced to a minimum of 15 months.

As the victim’s father Michael told me: "I know nothing can bring Rhiannon back. But you do lose faith in the legal system." Cases need to be negotiated but every now and again there is a howler, such as the case of Constable Ben Ashmole, shot in the head in 2015 by career criminals Sam Liszczak and Rod Phillips. Sam Liszczak was charged after the shooting of police officer Ben Ashmole. Followed by Ashmole in a marked police car, they did a U-turn and fired a shotgun at him from less than five metres. If he had not ducked he would have been killed instantly - instead he was hit by 14 pellets, 11 of which remain embedded in his skull. Even though a magistrate committed them for trial on attempted murder, which carries a maximum penalty of 25 years, intentionally causing serious injury (20 years) and recklessly causing serious injury (15 years), the backroom deal allowed them to plead to recklessly causing injury (five years).

They were sentenced to a minimum of four years on the shooting charge. We need plea deals but we also need those in the backrooms who deal the cards to remember that while it is a numbers game, each number represents a real victim. As Professor Freiberg admits: ‘‘What is missing is the voices of victims. We would love to rectify that in future research.’’