Accused lit fire to 'bump' Qld ref: court

A man accused of murdering a Brisbane rugby league referee told undercover police he tried to "bump" his alleged victim off by starting a house fire to suffocate him, a court has heard.

Tyson John Taylor, 41, has pleaded not guilty to the execution-style murder of Brisbane rugby league referee Tony McGrath at his home in May 2013.

He is also defending an attempted murder charge stemming from a fire at the Woolloongabba property in October 2012.

A Supreme Court jury in Brisbane heard more covert recordings on Wednesday, including one in which Taylor told undercover officers posing as members of a crime gang he lit the October blaze after an attempt to fatally drug Mr McGrath didn't work.

The jury heard he did it to "bump" the retired accountant off because a woman called Susan Stewart, a prostitute to whom Mr McGrath was supposedly engaged, had asked him to.

"She wanted me to get rid of him," he said.

As they rode in a car, Taylor described to the officers buying 30ml of GHB beforehand to give to Ms Stewart, intended to be put into Mr McGrath's drink.

Later, Taylor told the officers he waited for Mr McGrath to stop breathing only to later set a curtain alight thinking the smoke would suffocate the unconscious man.

"Once the curtain took light I just walked out," he said in the recording.

The court heard Ms Stewart was annoyed to learn Mr McGrath survived the fire.

In the recording, Taylor also told the officers he didn't know anything about Mr McGrath's estate before he died.

"It probably would've made it easier to do ... knowing there was a reward for it," he told them.

"That someone was actually gaining from it."

The crown alleges Mr McGrath's fiancee Ms Stewart believed she was set to inherit his estate and had received more than $550,000 from the late man before he died.

But the jury has heard changes to his will were never officially finalised.

The trial before Justice Martin Burns continues.