What Is the De Simoni Principle in Sentencing in Criminal Offences

The De Simoni principle in sentencing offenders stems from a 1981 case, R v De Simoni, involving a break-in that led to a controversial charge. This principle still guides criminal lawyers in Canberra Courts and Courts in the rest of Australia even today.

In 1979, Mr De Simoni broke into the home of Florence Kathleen Scott, an elderly woman. The defendant De Simoni stole $180 from Scott and struck her with a piece of wood, which was an ‘agreed fact’ of the case. The charge against him was for robbery, for which he pleaded guilty.

De Simoni was dependent on narcotics and had taken to breaking into homes to steal to fund his habit. When De Simoni broke into Scott’s house, the latter surprised him. It resulted in an altercation—when De Simoni realised that he struck an older woman, he showed remorse, helping her to a chair and calling for help before fleeing.

Because of the injury to Ms Scott (or wounding of the elderly woman), Mr De Simoni’s charge could have been aggravated robbery, a more serious offence with a harsher maximum penalty. Wounding is an aggravating feature for robbery under the specific offence provisions he was charged with and so he could have instead been charged with aggravated robbery instead of robbery.

The sentencing judge imposed a harsher penalty because of the wounding aspect, treating it in effect as an aggravating feature of the offence. This was legally problematic because Mr De Simoni only pleaded guilty to robbery, and not aggravated robbery due to wounding. His case eventually reached the High Court, which found the sentencing judge to have committed a legal error in considering the wounding in the penalty

The High Court also maintained that the judge should not have accepted the wounding as an ‘agreed fact’, as this presupposed the filing of an aggravated robbery charge.

The De Simoni principle gives criminal solicitors and criminal lawyers both a potential strategy that benefits their client and also something which it is crucial to be borne in mind when an offender pleads guilty to an offence. If the defence can sucessfully negotiate with the prosecution to accept a guilty plea to a lesser charge, it may come with an amendment of the statement of facts (ACT) or facts sheet (NSW) which removes a reference to facts which would amount to a more serious offence. It would also prohibit the leading of evidence of conduct or facts that would make the allegations for which the offender is being sentenced amount to a more serious offences.

For instance, a skilful criminal lawyer could negotiate a deal, where a person charged with assault resulting in bodily harm will plead guilty to the lesser charge of common assault. If this occurs, the court cannot receive evidence of any injury amounting to actual bodily harm to the victim.

As such, in a case of a plea to a lesser common assault charge, the prosecution must strike from the facts any references to injuries such as black eyes, bruising, cuts, abrasions, and the like. Similarly, a lawyer can negotiate to downgrade a charge of deemed drug supply to ‘drug possession’ which would mean that the circumstances surrounding what may amount to a deemed supply must not be led by the prosecutor.



In all, the De Simoni principle means that a magistrate or Judge cannot consider an aggravating factor of an offence if it forms the basis for a more significant charge. This therefore requires prosecutors to lead facts that prove only the lesser charge.

Knowledge of practical applications of principles like De Simoni is a skill you gain only from having extensive experience in criminal cases and in court proceedings. A person who had been charged with a serious offence should consult with a criminal lawyer or criminal attorney who knows how to interpret and apply foundational cases like these in various circumstances.

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