Last month Judge Phillippa Cunningham sentenced Fidow to nine months' home detention for the attack. The maximum penalty for aggravated robbery is 14 years' jail but he is serving his home detention at a drug and alcohol treatment facility.
However he could still serve jail time - which Mrs Sutcliffe supported.
The Herald can reveal that on Monday the Crown filed a notice of appeal regarding Fidow's sentence.
"The grounds of appeal are that the sentence is manifestly inadequate and wrong in principle," said Crown Law spokeswoman Jan Fulstow.
"The appeal was filed in the Court of Appeal and no hearing date has been set yet."
Crown solicitor Simon Moore, QC, said as the appeal meant the case was back before the court, he was limited in what he could say.
"But I can make the observation that the threshold for the Crown to succeed on a sentence appeal is set higher than for the defence which explains, at least in part, why the Crown does not appeal sentences as often as sentenced prisoners," he told the Herald.
"The role of the Crown is to ensure sentencing levels are monitored and, where necessary, appeals are brought for the purpose of achieving consistency and creating a precedent or guideline for judges in future cases."
Mrs Sutcliffe was being supported by the Sensible Sentencing Trust.
Spokeswoman Ruth Money said she congratulated the Solicitor-General for allowing the Crown to appeal. She said Fidow's original sentence was "grossly inadequate".
"The crime was nothing short of a premeditated, violent attack on a vulnerable 81-year-old victim. We believe the sentence should have been at least five years as well as reparation paid immediately to the victim," she said.
Fidow has been ordered to pay reparation of $600 to Mrs Sutcliffe in weekly instalments - which start after his sentence ends.
Ms Money said judges should be held accountable for their decisions.
"Now the taxpayer is spending more money to ensure justice is served - that cost should be the judge's, not the taxpayers'."
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