Breaking down Erin Patterson’s sentence in Australia’s mushroom murders case

In Victoria, the maximum penalty for murder is life imprisonment and the maximum penalty for attempted murder is 25 years’ imprisonment. At a sentencing hearing on 25 August 2025, Justice Beale heard arguments from the prosecution and the defence about the appropriate penalty. Both parties agreed that the offending fell into the worst category for murder and attempted murder and that Patterson should receive the maximum penalty for both offences.

This sentencing outcome, and the agreement between the parties, is unusual. Maximum penalties are rarely imposed because they represent the absolute worst type of offending for a particular charge. The main point of contention was whether Justice Beale should impose a non-parole period, which is the minimum amount of time someone must spend in gaol before being eligible for release. The decision to release is not made by the Court but by the Adult Parole Board of Victoria.

On 8 September 2025, Justice Beale allowed his sentencing judgment to be livestreamed. He sentenced Patterson to 25 years’ imprisonment for the attempted murder and life imprisonment for the three murders, and imposed a 33-year non-parole period. The offences are to be served concurrently.

Section 11A(4)(a) of the Sentencing Act 1999 (Vic) requires that, when sentencing someone to life imprisonment, the Court must fix a non-parole period.

This means that, 33 years from the date Patterson entered gaol, she will be eligible for parole. This does not mean she will automatically be released. She must apply to the Adult Parole Board, which will decide whether she should be released. Serving her sentences concurrently means that they are all served at the same time.

In his Honour’s judgment at paragraphs [49] to [55], he identified six aggravating factors, being circumstances that made the offences more serious:

1. Substantial premeditation: Patterson had put significant thought into how she would murder her guests at lunch.

2. Post offending behaviour: She deliberately concealed that the mushrooms were foraged, claiming they came from Woolworths and an Asian grocery. Had she admitted they were death cap mushrooms, an antidote may have been administered earlier.

3. Victims’ suffering: The victims endured protracted and severe effects from the poisoning, requiring sedation and medical ventilation.

4. Indirect victims’ suffering: Patterson’s offending had profound effects not only on the victims but on many others.

5. Elaborate cover-up: She attempted to conceal her actions by disposing of plates, faking illness, discarding the dehydrator, lying about helping health authorities, discarding her phone, providing a dummy phone, and lying in her police interview.

6. Betrayal of trust: All of Patterson’s victims were relatives by marriage who attended the lunch because of their family relationship. She exploited that trust to lure them with the intention of poisoning them.

Justice Beale also considered Patterson’s personal circumstances, including her background, whether she had a prior criminal record, remorse, conditions in gaol, and any relevant reports such as psychological or psychiatric assessments.

Remorse means being sorry for what you have done, shown by acknowledging your actions and recognising their impact. Patterson maintained her innocence, insisting she had done nothing wrong. Justice Beale found there was no evidence of remorse at paragraph [89]. Unusually, Patterson’s lawyers presented very little in mitigation at the sentencing hearing, relying largely on what she had said during the trial about her personal history at paragraph [72].

Justice Beale also considered the purposes of sentencing, which are set out in section 5(1) of the Sentencing Act. These purposes are:

• To punish the offender to the extent and in a manner that is just in all the circumstances

• To deter the offender or others from committing offences of the same or a similar character

• To establish conditions that may facilitate the rehabilitation of the offender

• To express the court’s denunciation of the type of conduct involved

• To protect the community from the offender

• Or a combination of two or more of these purposes

At paragraphs [96] to [98], Justice Beale considered all of these matters but observed that Patterson’s rehabilitation took a backseat because of the gravity of the offending.

All other states have equivalent legislation outlining what must be considered when sentencing. It is important to have a lawyer who understands these provisions and can best prepare your case for sentence to ensure the best possible outcome.