Bradley Scott Purkiss is facing trial in the Hobart Supreme Court for the 2017 murder of Dwayne Robert Davies, co-accused with the victim's wife Margaret Anne Otto.

Both have pleaded not guilty.

Mr Davies was last seen on May 26, 2017, and his body was found in a shallow grave at Levendale wrapped in a blue tarp, bound with twine and tape, a week later.

It is alleged Mr Purkiss carried out the murder as part of a plan with Ms Otto.

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During his closing submissions on Thursday, Mr Purkiss' defence lawyer Alan Hensley said the Crown had failed to prove a motive for his client to kill Mr Davies.

"Mr Purkiss may have had some frustration with Mr Davies but he was still his best and only friend," Mr Hensley said.

"There might have been friction in their friendship but there was an affection between them."

Mr Hensley said there was no "love triangle" or evidence of any strong bond or friendship, more than Mr Purkiss being cordial to his friend's wife, between the two accused.

He also alleged the Crown's argument Mr Purkiss harboured resentment towards the victim over an outstanding debt "made no sense."

"Dead men can't repay debts," he said.

Mr Hensley alleged Ms Otto assisted "the real murderer" to frame Mr Purkiss.

"Bradley Purkiss is a pretty convenient fall guy," he said.

"[The evidence] is breadcrumbs deliberately left."

Mr Hensley said the fact Mr Purkiss' DNA was found on the twine and tape binding Mr Davies' body "doesn't mean anything at all."

"It's his tarp so you would expect his DNA on it. He uses it when he goes camping," Mr Hensley said.

Mr Hensley said the evidence showed a second person left their DNA on the twine wrapped around Mr Davies' body.

"There is at least one unknown actor on the stage here and their DNA pops up in all the important places," he said.

"It's obvious a crime has been committed here but there is no direct evidence Mr Purkiss murdered Mr Davies."

Mr Hensley said it was also important to consider where there was no DNA, saying it would be "astonishing unlikely", if Mr Purkiss had shot Mr Davies, there would be none of the victim's DNA on his clothes or any blood on Mr Purkiss or in the car he is alleged to have driven after the murder.

Mr Hensley told the jury they need to accept the state proved beyond reasonable doubt their case was the only explanation if they deliver a guilty verdict.

"In circumstantial cases there is a very real risk of injustice," he said.

"The thing about circumstances is when you go looking for them you find them."

Chief Justice Alan Blow told the jury they could find one, both or neither of the accused guilty.

"It's not an all or nothing thing. You need to consider the evidence against each of these two people separately," Chief Justice Blow said.

The jury will begin deliberating on Friday.

Due to the large volume of evidence in the trial, Chief Justice Blow said a court in Hobart would be used as an extension of the jury room to deliberate.