Alan Jones' comments could be defamatory

A Supreme Court judge says he's "pretty sure" some statements made by radio host Alan Jones about Queensland's Wagner brothers are going to be found to have been defamatory.

John, Denis, Neill and Joe Wagner are seeking $4.8 million in damages from Jones, Harbour Radio, 4BC and journalist Nick Cater over 32 broadcasts in 2014 and 2015.

The final witnesses gave evidence in the Brisbane Supreme Court on Wednesday.

Justice Peter Flanagan then asked the opposing barristers to work together to reduce the number of alleged imputations, or comments with a defamatory meaning, from more than 90.

"Work out what imputations should be sensibly abandoned, what imputations should be sensibly admitted and then I can actually decide what are the true disputes in this case," he said.

"What broadcasts do not properly identify all plaintiffs and what broadcasts properly identify all plaintiffs."

Justice Flanagan then made an observation about the allegations.

"As for the imputations that are agreed to arise, I'm pretty sure they're going to be defamatory aren't they?" he asked.

"From what I've heard of this trial."

It is unknown what comments Justice Flanagan was referring to.

The Wagner brothers claim the broadcasts accused them of the deaths of 12 people in the town of Grantham during the 2011 Queensland floods, when one of the walls of the Lockyer Valley quarry they owned collapsed.

They claim they were also subjected to constant abuse, including accusations of a high-level cover-up with politicians, corruption and intimidation relating to their Wellcamp Airport.

Closing arguments from both parties will start on June 13.