Dr Andrew Mubiru, the eighth witness the prosecution put to the stand a month ago, remains the subject of intense cross-examination by the defence team - for many reasons.
The Director of Forensics Services stepped out of the standard operating procedures in criminal investigation to irregularly collect own DNA samples and use include them in the trove of evidence in murder trial of Ms Molly Katanga.
Dr Andrew Mubiru, the eighth witness the prosecution put to the stand a month ago, remains the subject of intense cross-examination by the defence team - for many reasons.
As the trial of Ms Katanga resumed before Justice Isaac Muwata of the Criminal Division of the High Court, the defence team continued to pick him apart as they made every push count in their attempt to prove that she was more of a domestic violence victim than a killer.
Ms Katanga is accused of murdering her husband Henry Katanga on November 2, last year.
Taking the witness stand on Tuesday, Mubiru faced an unrelenting MacDosman Kabega, who on another day would pass for Gerrie Nel, the South African known in court circles as the "bull terrier" for his reputation for being ruthless and merciless in his bid to get to the truth.
As the defence picked him apart, Mubiru admitted to using and examining samples he collected himself from the trigger of the suspected murder weapon and the various sticks collected from the scene.
The forensics examiner told the court that the police had not supplied him with any samples.
The defense lawyers suggested that Mubiru acted beyond the scope of the instructions given to him by police investigators regarding the samples to be tested for DNA in the case.
The defense also pointed out to the court that since Mubiru admits that the swab he took from the trigger of the pistol was consumed in the laboratory, there is no exhibit of such a sample before the court.
Mr Kabega then closed the defense team's cross-examination but notified the court that at an appropriate time, during the visit to the scene of the crime at the Katanga home on Chwa II Road in Mbuya, Mubiru would be recalled for further cross-examination.
The trial continues to unfold, with the prosecution expected to call additional witnesses to support their case, while the defense maintains a focus on procedural lapses and the handling of forensic evidence.
Mubiru's chequered science
Last week, defense attorneys raised concerns about potential discrepancies in forensic evidence analyzed by Mr Mubiru.
Kabega accused him of examining a gun from a different case, not the alleged murder weapon. Counsel Kabega presented startling evidence, suggesting Mubiru analysed a pistol with a different serial number, contradicting the prosecution's claims.
"Do you agree that each gun has specific serial numbers identifying it and distinguishing it from another?" Kabega pressed.
Mubiru insisted he only examined what was submitted to him for analysis.
"My lord, I'm not a ballistic expert," he said.
However, Kabega alleged Mubiru examined a gun from a different case, citing a judgment from the Court of Appeal case, Uganda Vs Kato Kajubi.
"From the evidence supplied to us by the prosecution, it's evidence that scenes of crime officers took swabs from a number of exhibits. Those swabs were supplied to you on police form 17A, but you were not supplied with the swab of the barrel of the gun, fingers of the deceased, trigger house of the gun, but you went ahead and made findings in your report," Kabega said.
He also pressed Mubiru on whether he was supplied with enough materials to conduct the required analysis.
"Now, in your view, Mr Mubiru, did the police provide you with sufficient material to carry out what you wanted to?" Kabega added, to which Mubiru struggled to answer.
"I dealt with what they gave me; I don't know whether they were sufficient or not," said Mubiru.
Kabega also said exhibits and items were deliberately left for analysis because they would reveal that A1 (Ms. Molly Katanga) was badly assaulted.
Lawyers and other experts have previously urged that Molly is a victim of domestic violence.
"You were at the scene of crime; these were items of assault, and you didn't do a DNA. I want to suggest to you that you deliberately left them because they would reveal that A1 was badly assaulted," said Kabega.
Evidence on court record shows that a shocking array of weapons was recovered from the master bedroom of Molly and Henry Katanga, including four sticks, a baton, and a pistol.
On Wednesday, August 28, Mubiru, Acting Director of Forensic Services, revealed the disturbing details during cross-examination, confirming that Molly's blood was found extensively throughout the bedroom, bathroom, balcony, and ceiling, with gruesome pieces of her skull and skin discovered on the bedroom door hinge.
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The court was shown the exhibits, which included three wooden sticks, a wooden baton, and a metallic walking stick with a curved handle.
A pistol was also recovered from the scene, which Mubiru described as an "armory."
Kabega also presented additional evidence, seeking to cast doubt on the prosecution's case. Kabega tendered hard copies of the software used in Mubiru's examination analysis, highlighting that the software was outdated and prone to inaccuracies.
He also referenced the crime scene procedure manual management by the Directorate of Forensic Services, which Mubiru admitted to during cross-examination.
Kabega aimed to demonstrate non-compliance with procedural guidelines for handling evidence, potentially leading to contamination within the lab.
Molly Katanga is charged with the murder of her husband while her daughters Patricia Kakwanza and Martha Nkwazi, their shamba boy George Amanyire, and nursing officer Charles join her in the dock as accomplices after the murder.
