Defence lawyer Charles Mercieca on Saturday devoted much of his closing address in Yorgen Fenech's murder trial to challenging the credibility of state witness Melvin Theuma.

Mercieca repeatedly questioned Theuma's changing accounts, the recordings he handed over to police and others he claimed to have destroyed, as well as the circumstances in which he was granted a presidential pardon.

Mercieca was addressing jurors after prosecutor Anthony Vella, in his closing arguments on Friday, maintained that the evidence firmly proved Fenech commissioned and financed the October 2017 car bomb attack which killed Daphne Caruana Galizia, a columnist with The Malta Independent.

Fenech has pleaded not guilty to two principal charges: complicity in the wilful homicide of Daphne Caruana Galizia and criminal association to commit the murder.

With the defence bringing its closing arguments to an end, Judge Edwina Grima will address the jurors on Monday before they deliberate on the verdict.

In his address Saturday, Mercieca questioned why Theuma had been promised a pardon before Fenech was arrested and why such extensive immunity was necessary if investigators already possessed the recordings that formed a central part of the case.

Mercieca argued that Theuma was granted immunity not only in relation to the murder plot but also in connection with other crimes. He described this as a matter the jury should scrutinise when assessing Theuma's credibility.

The lawyer also questioned why authorities had waited until November 2019 to arrest Theuma when, he said, Europol had sought his arrest months earlier.

A central theme of the defence address was Theuma's reliability as a witness.

Mercieca pointed to occasions when Theuma had given different accounts of events, including his contacts with Fenech and then OPM chief of staff Keith Schembri. He also questioned Theuma's claims about his visits to Castille and the purpose of meetings there.

One such meeting, Mercieca said, lasted around two and a half hours. He asked the jury what had happened during that period of time.

The defence lawyer argued that Theuma had retained some recordings while others were missing, saying the absent material was potentially significant.

Mercieca suggested that Theuma had been selective about the material he handed to investigators and questioned what had happened to recordings involving Schembri and others.

The defence also relied heavily on what Mercieca described as contradictions between Theuma's evidence and documentary material.

He pointed to Fenech's passport records to challenge the prosecution's chronology concerning the commissioning of the murder. Mercieca said the passport showed Fenech was in the United States on April 6, 2017, and in Dubai in early May.

He argued that there was no evidence placing Fenech in Malta during the relevant period, while there was evidence that Theuma had met Schembri at Castille.

The defence also challenged the prosecution's suggestion that the Electrogas project provided the motive for the assassination.

Mercieca argued that information concerning the alleged leak only emerged after the murder, and questioned why the prosecution had placed such emphasis on Electrogas when, in his view, the chronology did not support it as the primary motive.

Another major strand of Mercieca's closing address concerned Schembri.

The lawyer repeatedly argued that the evidence pointed towards Schembri and questioned why, in his view, investigative attention had not followed that trail sufficiently.

At one point he told jurors that "all roads and bridges leading to Keith Schembri were burnt", urging them to weigh evidence both for and against the accused rather than accepting the prosecution's interpretation.

Mercieca also focused on wording in another document concerning Theuma's alleged government job. He argued that the use of the singular when referring to what Schembri had obtained was significant.

From this, he argued that Schembri was the person who had obtained what he wanted.

The defence also raised questions over political and police connections surrounding Theuma.

Mercieca referred to allegations concerning leaks of recordings and information about impending police raids, and questioned the role of former police commissioner Lawrence Cutajar.

The defence lawyer highlighted a police analysis of electronic data in which conversations between Theuma and Johann Cremona, Fenech's business partner, were described as portraying Fenech as an addict and weak link.

Mercieca also challenged Cremona's role, asking whether his involvement was simply to meet and calm Theuma or whether there was more to his relationship with the middleman.

The €30,000 payment to hitman Vince Muscat was another point raised by the defence. Mercieca questioned why the payment had been made before the election and highlighted testimony that Theuma had paid the money himself.

The defence also addressed Fenech's decision to leave Malta.

Mercieca argued that Fenech had reason to fear both Schembri and Theuma, whom he described as having access to the police commissioner.

He said Fenech had been caught between the two men.

Mercieca acknowledged Fenech's personal failings, including his drug problem, but stressed that these did not make him a murderer and were not the matters on which he was being tried.

He also pointed out that Fenech had sought a confrontation with Theuma in 2019, countering the prosecution's criticism that no such confrontation had taken place.

The defence challenged the prosecution's characterisation of Theuma as an anxious and uncalculating middleman.

Mercieca argued that Theuma's discussions about 17 Black, journalists and other matters demonstrated that he understood what he was doing.

He also questioned why Theuma had retained a photograph of Schembri in an ice-cream box during the period surrounding his arrest.

The defence's broader argument was that the jury should not be required to accept Theuma's version of events simply because he had been granted immunity.

Mercieca repeatedly reminded jurors that the burden of proof rested with the prosecution and that the defence did not have to prove an alternative version of events.

He argued that where the prosecution's evidence raised reasonable doubt, the defence was entitled to rely on that doubt without having to establish that its own explanation was conclusively true.

Mercieca listed what he described as significant gaps, including missing phones, deleted WhatsApp chats, missing electronic material and evidence that had not been properly pursued.

He argued that police had seven years to investigate the murder and that the jury should consider what had not been found or explained as well as the evidence presented in court.

Mercieca said the prosecution had failed to provide clear answers to the defence's core questions and argued that unanswered questions and doubt were incompatible with legal certainty.

Mercieca then turned to the police search of Keith Schembri's home. He questioned how officers could claim to have collected everything when evidence showed that lead investigator Keith Arnaud had looked directly at a table where Schembri's mobile phone was sitting and said he was not seeing anything.

He next challenged the prosecution's interpretation of statements made by Yorgen Fenech during the investigation, saying they did not amount to an admission of guilt. Mercieca stressed that Fenech had consistently maintained that he had never ordered, paid for or wanted the murder of Daphne Caruana Galizia. He described Theuma's evidence as "a mountain of lies".

Mercieca then questioned the alleged government job given to Theuma, arguing that Schembri had arranged the position so that Theuma effectively did nothing.

The defence subsequently raised questions about the events involving Vince Muscat and Alfred Degiorgio. Mercieca referred to police interrogations in which investigators repeatedly questioned Muscat about whether the murder would have happened if Theuma had not become involved. He contrasted this with what he described as the prosecution's willingness to accept Theuma's account.

Mercieca returned to the recordings made by Theuma, arguing that during two years of recordings there was not a single occasion when Theuma directly told Fenech that he had been sent to the Degiorgios by him.

The lawyer also challenged the prosecution's financial motive theory, questioning whether Fenech would have wanted Caruana Galizia killed over the Electrogas project. Mercieca instead argued that the evidence pointed towards Schembri's hostility towards the journalist and what she had written about him.

He also discussed the German authorities' response concerning Caruana Galizia's laptop and storage disks, telling jurors that her family had requested that the data on the devices be deleted.

As he approached the end of his address, Mercieca returned to Schembri, asking jurors to consider the political events surrounding the case. He urged them to rely on their own judgment and to vote according to what they considered just and truthful.

Mercieca ended by asking jurors to consider whether they could honestly believe Theuma in light of his conflicting accounts. He said he could not believe the state witness and argued that something in the case did not make sense.

In his final appeal, Mercieca told jurors that the decision was now theirs and asked them to review all the evidence and determine whether the prosecution had proved its case beyond reasonable doubt.

Judge Edwina Grima suspended proceedings, with the jury address due to begin on Monday.

A minute-by-minute account of the defence's address may be found here