Glenn Weaven

Death of Mary-Lou Cook

In the early hours of December 14, 2008, the body of Mary-Lou Cook was discovered badly burned in her Narre Warren home, which had been deliberately set on fire. An autopsy later revealed that Ms. Cook had died from a stab wound to the neck, and the prosecution claimed the fire was started to destroy evidence. In 2009, Glenn Weaven, a friend of Ms. Cook, became the focus of a "Mr. Big" covert operation, during which he allegedly made admissions to undercover operatives regarding the crime and the location of the murder weapon. He was convicted of her murder in 2011.

BOHII began reviewing Glenn’s conviction in 2015, raising concerns about the reliability of his alleged confession and the ethics and legality of the undercover police operation that played a key role in his conviction.

Several critical errors in the police investigation have been identified by BOHII, which cast doubt on Glenn’s guilt:

Alternate suspects not considered 

The police investigation failed to thoroughly explore other potential suspects with a motive to harm Ms. Cook. A key figure that was overlooked is a now-deceased neighbour with a history of conflict with Mary and her family. This individual had threatened to "run-through" her house the night she was killed, a term suggesting a rehearsal for a criminal act. The same neighbour had previously threatened to kill Mary’s daughter, and Mary’s son took out a restraining order against him due to aggressive behaviour. With a criminal record that included charges such as threat to kill, recklessly causing injury, and intentionally destroying property, this neighbour should have been considered a person of interest. Glenn, on the other hand, had no history of violence.

The ‘Mr. Big’ operation 

The ‘Mr. Big’ operation is a covert police investigation technique designed to elicit confessions from suspects of serious crimes. Undercover officers pose as members of a fictional criminal organisation, befriending the suspect and gradually involving them in seemingly illegal activities. The suspect is promised greater rewards and protection from legal consequences if they can demonstrate loyalty and honesty. The operation culminates in a staged meeting with the “boss” of the organisation, known as “Mr. Big.” During this meeting, the suspect is encouraged to confess past crimes in exchange for membership or assistance. However, these operations have been criticised for potentially leading to false confessions due to the psychological manipulation involved. 

The use of the Mr. Big technique in this case resulted in significant inconsistencies and gaps in the investigation being overlooked after Glenn’s confession. Concerns have been raised regarding the exploitation of Glenn’s fragile mental state, suggestibility, and the coercive tactics used by police, including financial incentives. As the crux of the prosecution’s case rested almost completely on this admission, the reliability of Glenn’s confession is questioned, considering he was also intoxicated and suffering from an allergic reaction at the time. 

Given these factors, it’s likely that, paired with the immense pressure, Glenn may have said whatever was necessary to satisfy the demands of the undercover officers and escape the stressful situation, casting serious doubt on the accuracy and validity of his statements. 

Futhermore, investigators failed to verify whether Glenn’s version of events exactly matched the evidence or facts of the case. By focusing solely on his confession, critical inconsistencies between Weaven’s story and the objective truth were left unexamined, weakening the integrity of the prosecution's case. In essence, the confession could have been filled with discrepancies or exaggerations, but without proper follow-up, it became the primary basis for prosecution despite the questionable circumstances in which it was obtained.  

The murder weapon 

During the final Mr. Big scenario, where undercover operatives were aiming to produce a confession, Glenn provided multiple accounts regarding the ‘murder weapon’. He claimed at different points that the knife broke at the tip, and the pieces were buried together, yet also scattered across various parts of Berwick. In the final ‘confession’ within the Mr. Big sting, Glenn claimed that he had disposed of the knife by burying it 12-18 inches underground in a specific location. Following this, Glenn then led the undercover officers to a location. This occurred at night, and a knife was not discovered until the following day. The knife discovered was visibly sticking out of the ground and had a broken handle. During the interval between Glenn revealing the location and the knife’s retrieval, the scene was neither secured nor monitored. Some officers present that evening have had a recorded history of corruption, thus raising questions about the possibility that the knife could have been planted at the scene. 

Further to the circumstances in which the knife was found, no forensic evidence links Glenn or Mary to the knife. There is no DNA evidence of either Glenn or Mary on the knife, and the measurements of the knife do not align with the dimensions of Mary’s stab wounds. The forensic pathologist who conducted the autopsy suggested “there is a reasonable argument that, based on the measurements, there is some doubt," about the knife found being the murder weapon. Additionally, the absence of any blood traces on the knife only adds to the uncertainty regarding its involvement in the murder. 

The use of the Mr. Big operation in this case raises serious questions about the reliability of Glenn's confession. Extracting confessions through psychological manipulation can lead to false or unreliable admissions and, together with the lack of meaningful corroborating evidence and crucial leads and inconsistencies left unexamined,  serious questions must be raised about the security of Glenn's conviction. 

‘Mr Big’ by Unravel (ABC)

Glenn’s case and the use of the ‘Mr Big’ technique are currently the subject of award winning ABC podcast Unravel.

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