Thief who killed Victorian jewellery store owner in front of his wife jailed for 27 years

A robber who was high on drugs when he killed a Victorian jewellery store owner in front of his wife has been jailed for 27 years.

Gavin Perry, 27, killed jeweller Dermot O'Toole as he rushed to protect his wife Bridget during the robbery in July 2013.

Perry was high on the drug ice and brandishing a knife when he burst into the Hastings shop, pushed Mrs O'Toole into a cabinet and stabbed Mr O'Toole as he lay helpless on his back.

Victorian Supreme Court Justice Elizabeth Hollingworth said Mrs O'Toole was forced to watch her husband die.

"She had to watch her husband of 41 years die in front of her as he came to her defence," she said.

Shortly before robbing the O'Tooles' store Perry purchased a large carving knife from a nearby supermarket.

"As soon as you encountered the slightest resistance from the O'Tooles you swiftly resorted to using the knife against them both," Justice Hollingworth said on Monday.

She said CCTV footage of the robbery showed Perry acting in a frenzied manner consistent with someone on the drug ice.

The only explanation Perry offered was that he had been abusing drugs.

Justice Hollingworth said Perry would continue to be a person who posed considerable risks to the community unless he undergoes treatment for his addiction.

Perry was on parole when he committed three armed robberies in six days - the final crime targeting the O'Tooles' jewellery shop in Hastings on July 12, 2013.

He had been released from jail in early 2013, after serving four years of a six-year term for armed robbery offences.

Justice Hollingworth said he had also breached community based orders and intensive correction orders stemming from his more than 200 criminal convictions.

"The number of them further demonstrates your disregard for the law," Justice Hollingworth said.

Perry pleaded guilty to murder, intentionally causing injury and three counts of armed robbery.

He must serve 23 years before he is eligible for parole.