There are now two appeals in the Erin Patterson mushroom murder case. What’s going on?

The Victorian Director of Public Prosecutions, who has carriage of the Erin Patterson murder case, has chosen to appeal against what he considers to be an overly lenient sentence.

This comes on the back of news last week the convicted murderer has instructed her lawyers to institute an appeal against her conviction.

These appeals could extend the life of the high profile case, or it could all quickly fizzle out. Here’s what’s happening now and what comes next.

From lunch to a life sentence

In September, Patterson was sentenced on three counts of murder and one count of attempted murder for serving a beef Wellington filled with poisonous mushrooms to guests at her home in regional Victoria in July 2023. It followed a lengthy, notorious trial.

Victorian Supreme Court Justice Christopher Beale ordered a life sentence with a non-parole period of 33 years. Given her age (50) and the time she’d already spent in detention, Patterson will not be eligible to apply for parole until 2056, when she is in her 80s.

The law typically gives both the prosecution and the defence 28 days after the sentence to lodge any appeal.

This period would have expired Tuesday October 7, but both legal teams have sought an extension of a further 28 days under a new process that came into operation (on a trial basis) at the end of last month. This allows for a total of 56 days (28 days plus the extended 28 days) if the initial notice of appeal is filed within the first 28 days.

This is what both teams are now doing, but for very different reasons.

Patterson’s appeal

Erin Patterson has a new team of barristers, not only high profile lawyer Julian McMahon, but also well known criminal law academic and writer Richard Edney.

Under the Victorian Criminal Procedure Act, any person seeking to appeal a conviction or sentence must first seek leave to appeal. This basically means permission to appeal.

The matter of leave is heard by a single judge of the Supreme Court. This judge will determine whether there is sufficient merit in the appeal grounds (reasons) to warrant convening a full hearing of the Court of Appeal.

The judge could grant such leave to Patterson to appeal against her conviction on any or all of three grounds.

The first is where the verdict of the jury is deemed unreasonable and not supported by the evidence.

This was the ground successfully sought in the George Pell appeal verdict, where the High Court determined his convictions were unsound. The High Court decided it was not open to the jury to find Pell guilty beyond reasonable doubt.

A second ground is that the trial judge insufficiently directed the jury’s attention to the defence case in the summing up. This is highly unlikely to be raised in the Patterson appeal.

A third ground is where there has been a substantial miscarriage of justice in the course of the trial. Typically this argument is based upon a defence submission that something has been allowed into evidence (by the trial judge) which should not have been introduced, or that something was not allowed into evidence (excluded by the trial judge) which should have been admitted into evidence.

One can strongly speculate that this is where the defence’s appeal submission will proceed.

The prosecution’s appeal

Either party can appeal the sentence. Thus the prosecution must also get leave to appeal from a judge to advance its case.

In this case the prosecution is now seeking to do so, and will need to submit that the sentence is obviously – not merely arguably – overly lenient.

As Patterson was given three life sentences (to be served concurrently), the prosecution will argue that a 33 year non-parole period (not unusual in cases of single homicides) was clearly inadequate.

It’s highly improbable the defence will cross-appeal the severity of the sentence, given it is at the lower end of what a triple murderer could have expected to receive.

Read more: Four victims, no remorse: Erin Patterson given a life sentence for mushroom murders

What happens if the appeals are allowed?

If the defence appeal against conviction is allowed, the court may either acquit Patterson or send the whole case back for a retrial.

In the case of a successful appeal against sentence by the prosecution, the appeal court can either impose a longer non-parole period, or send the matter back to the trial judge for a re-sentencing.

There will be much to observe in the next phase of the criminal justice process. The first hurdle for Patterson is to get leave to appeal. At that hearing we will know for the first time where the appeal arguments are headed, and indeed, whether anything will further unfold.