Chaos in Qld court amid murder conviction

The Supreme Court is investigating alleged threats against a Brisbane jury that convicted a man of murdering his stepdaughter.

Raymond John Mead, 52, was found guilty on Tuesday of murdering Sherelle Locke while she was watching TV with her mother in Boronia Heights in February 2014.

At one point, he claimed to have slipped and fallen, accidentally stabbing the 23-year-old.

As the guilty verdict was delivered, a woman stormed out of the courtroom and shouted "she deserved it".

It is believed the same woman threw water at a security guard in the courthouse corridor.

Justice Ann Lyons said she was very concerned a member of the public made threatening faces to the jury as they left the courtroom.

The incident is being investigated.

Mead's supporters cried as he was taken away by several corrective services officers.

The court had heard Mead detested Ms Locke and openly blamed her for the ongoing problems in his marriage.

Mead told a neighbour just weeks before Ms Locke's death that if she stuffed up again she would "get what's coming to her".

"If I could stab Sherelle and get away with it I would," Mr Mead told the neighbour.

Ms Locke's mother Marlene testified Mead had been drinking heavily the day he pinned her daughter down and grabbed her by the throat.

"I thought he just hit her in the chest," Mrs Locke said.

"All I could see was her out the corner of my eye begging me for help until she wasn't talking any more," she said.

Outside court, Mrs Locke said she was pleased with the guilty verdict but nothing would bring back her daughter.

"There's always a piece of my heart missing," she said.

Mead initially told police Mrs Locke had stabbed Sherelle but at trial claimed he had fallen and accidentally plunged the knife into the young woman's chest.

He will be sentenced on August 15 for her murder as well as grievous bodily harm done to Mrs Locke.