A witness denies he is responsible for the murder of two people drowned in a toolbox, rather than three men facing trial for the alleged crimes.

Stou Daniels, Davy Malu Junior Taiao and Trent Michael Thrupp are charged with murdering Cory Breton, 28, and Iuliana Triscaru, 31, at Kingston in Logan, south of Brisbane, on January 24, 2016.

Lelan Harrington today told a Queensland Supreme Court jury he was not present when a large toolbox containing Breton and Triscaru was thrown into a lagoon.

Defence barrister for Thrupp, Jessica Goldie, asked Harrington if he was lying when he said her client told him he killed the alleged victims.

“I suggest to you at no stage has Mr Thrupp ever made comments to you about shooting Mr Breton and Ms Triscaru and you just completely made that up,” Goldie said.

“No, that’s exactly what he said,” Harrington said.

Goldie asked Harrington about his previous statement that, hypothetically, he would have shot the pair in the head. 

“That is the truth, isn’t it? You are responsible for what happened to Mr Breton and Ms Triscaru?” Goldie said.

Crown prosecutor Nathan Crane previously told the jury he would allege Daniels and Taiao were liable for murder by forcing the alleged victims into the toolbox at a residential unit at Kingston in the hours before their death.

Thrupp either threw the toolbox into nearby Scrubby Creek or was present when it happened, Crane said. 

Harrington agreed he was given a suspended sentence for detaining and assaulting Breton and Triscaru after agreeing to give evidence for the prosecution.

He admitted lying to investigators in February 2016 to conceal the defendants’ alleged suspicion the alleged victims were informing police about their drug dealing.

“Yes, I did lie for them so they did not go to jail,” Harrington said.

All three defendants pleaded not guilty to two murder charges at the start of their trial on Monday.

During his second day giving evidence, Harrington, a flatmate to some of the defendants, continued being cross-examined by defence barristers.

He admitted he initially lied to police in an effort to protect his friend, named as a chief offender by Crane, from being charged with murder.

“I said ‘f— it’ and then told the truth,” Harrington said.

He denied holding a grudge against Breton over claims he assaulted someone close to him when they could not pay for drugs.

Justice Glenn Martin had to repeatedly warn Harrington he needed to listen to each question and give answers.

Harrington told the jury he was sure about his testimony about Taiao assaulting Triscaru in the hours before her death.

“You saw a cable tie placed around her neck by my client?” barrister Lars Falcongreen said.

“I have got a clear picture of that,” Harrington said.

The trial continues before Justice Martin.