The murder of Jaidyn Leskie occurred in 1997, believed to have been caused by head injuries. Leskie's body was found at the Blue Rock Dam, near Moe, Victoria, Australia, on 1 January 1998, six months after his disappearance from a Newborough home. A child of Bilynda Murphy (now Williams) and Brett Leskie, Leskie's murder remains unsolved, despite intense public interest, several leads, and the arrest and 1998 trial of a prime suspect, Greg Domaszewicz (), Murphy's boyfriend, who was acquitted of murder, following a trial by jury.

A decision was made in 2002 not to hold an inquest into the toddler's death and the case remained in the news for several more years. An inquest was later held in 2006, implicating Domaszewicz, who at the time of the kidnapping was babysitting the child. The exact circumstances of Leskie's disappearance and death were never clear, and were complicated by vandalism at the house on the evening of the toddler's disappearance; several false tips and pranks about the child's fate; and the body not being discovered until six months after his disappearance.

Disappearance At the time of his disappearance, Jaidyn Raymond Leskie (30 April 1996 – 15 June 1997) was aged 13 months and two weeks old and lived in the town of Moe with his mother Bilynda Murphy and his older sister. Leskie's father, Brett, was separated from Murphy and was residing in another state at the time of his son's disappearance.

Investigation On the night of his disappearance, Leskie was in the care of Greg Domaszewicz, while Murphy went out with her sister. Domaszewicz had been minding Leskie during the day, at his Newborough home, and was originally meant to drop the child home to his regular babysitter at 4pm; however, Domaszewicz never arrived and, despite several attempts, Murphy was unable to get into contact with him. Murphy assumed that Domaszewicz would care for the child throughout the evening and decided to keep her plans with her sister.

Around 2:30am, Domaszewicz left Newborough to pick up an intoxicated Murphy from Ryan's Hotel in the neighbouring town of Traralgon (approximately 20-minutes drive each way). After returning to Moe at around 3am, Domaszewicz dropped Murphy at her home, later returning at approximately 5am to inform her of Leskie's disappearance and taking her to Moe Police Station to file a police report. Domaszewicz claimed that Leskie was abducted from his home after he left for Traralgon, stating that he left the child on the couch to avoid waking him. However, police alleged that Leskie had likely died several hours earlier and while in Domaszewicz's care.

Soon after Leskie was reported missing, local and state police launched an intensive, 20-day missing person's search. The search for Leskie was believed to have been the largest search since the disappearance of Prime Minister Harold Holt in 1967, leading national headlines to proclaim "Where is Jaidyn?". The search was unsuccessful, largely hampered by a lack of witnesses, false tips to police, and the extensive geographic area that needed to be searched.

Behaviour of Domaszewicz Domaszewicz's allegedly strange behaviour the night of Leskie's disappearance, during the trial and afterwards, was the focus of media and investigators. Domaszewicz claimed that he left Leskie home alone when picking up Murphy from Traralgon, and that Leskie was abducted before he returned. However, earlier that evening Domaszewicz had called Ryan's Hotel and told Murphy that Leskie had been taken to hospital for a minor burn. After picking her up, Domaszewicz further told Murphy that he had moved Leskie from Moe Hospital due to their substandard care, and that her son was now at Maryvale Hospital—near the town of Morwell. Maryvale Hospital was under construction at that time, and there was no possibility it would receive patients. Domaszewicz then refused Murphy's requests to be taken to Leskie, telling her she was too drunk and would be refused entry. As such, Murphy did not know her child was missing until several hours after she had returned home for the night, believing him to be in hospital. Later defending his claims of Leskie's hospitalisation as an ill-timed joke, Domaszewicz's comments regarding the child's whereabouts were viewed by police as an attempt to cover-up Leskie's death.

Little is known regarding Domaszewicz's movements between arriving home from Traralgon (around 3am) and reporting Leskie missing (around 5am)—he claims that he was searching for Leskie by himself around Moe, stating he believed the child had been kidnapped as a prank. Around 4am, Domaszewicz was pulled over by police and subject to a random breath test. Although he knew Leskie was missing at this time, Domaszewicz did not use this opportunity to inform police.

House vandalism From the outset, Leskie's disappearance proved a difficult investigation with no forthcoming witnesses and limited information. Further complicating the investigation was the state of the crime scene—while Domaszewicz was picking up Murphy, his home was vandalised: a severed pig's head was left on the front lawn and several windows were smashed. Police quickly ruled out any relationship between Leskie's disappearance, the vandalism and its perpetrators. Dubbed 'the pig's head team' by Domaszewicz's defence lawyer, Colin Lovett , police determined the vandalism was an unrelated act of revenge against Domaszewicz. Police quickly uncovered that this event was orchestrated by the brother of Domaszewicz's ex-girlfriend, Yvonne Penfold, allegedly in retaliation for Domaszewicz's violent treatment of Penfold. The 'Pig's Head Team' became potential witnesses for Leskie's whereabouts after 2:30am, and stated in police and media interviews that they did not hear any sounds of a child crying during their vandalism of Domaszewicz's home. The presence of the severed pig's head at the site of a child's disappearance also fuelled early, yet baseless, public speculation about satanic cults and continued to be referenced in media coverage as symbolic for the confusing and strange circumstances around Leskie's disappearance.

Regardless of quickly being ruled out as suspects, the Pig's Head Team attracted intense attention from media and true crime writers, with some alleging the police should have investigated more thoroughly. There were claims that the Pig's Head Team accidentally injured Leskie during their assault on the home, then kidnapped him to cover up their involvement and caused his death. Domaszewicz claimed that Penfold and the Pig's Head Team kidnapped Leskie as revenge for their failed relationship, panicked after the police became involved, and killed the child. However, there was no verifiable evidence to support such kidnapping theories, and several of these commentators have misrepresented forensic evidence or only offer unnamed witnesses to support their claims. Police maintained that Domaszewicz's home was merely vandalised with no evidence of break and enter, though they received criticism for not fingerprinting the home's interior. Claims of possible intruders were repeatedly refuted by the crime scene examiners, who testified that the glass on the windows was clearly undisturbed and the broken section was too small for an intruder to gain access.

Discovery On 1 January 1998, more than six months after he disappeared, Leskie's body was discovered by picnickers at the Blue Rock Dam, north of Moe. Leskie's body was floating on the surface of the reservoir. Approximately from where the child's body was discovered, police recovered a crowbar, baby's boots, a bottle, a bib, and a sleeping bag. Police alleged that Leskie's body had been wrapped in the sleeping bag and weighed down by the crowbar. Forensic testing on Leskie's body, that was preserved by the cold waters of the lake through winter, revealed a poorly bandaged broken arm, severe head trauma and the presence of the drug Benzhexol. The child's clothing was DNA tested in an effort to solve the crime; however, cross-contamination at the laboratory caused confusion in the case, leading the Leskie case to becoming an internationally discussed example of the fallibility of DNA testing in criminological research. Several claims were made that Leskie's body exhibited signs of being older than when he disappeared, fuelling speculation that he was abducted and kept alive for several months after his kidnapping. However, each of these claims was either refuted via scientific and medical evidence, or was based on unsubstantiated claims made by anonymous witnesses. Leskie's teeth, hair and size were also claimed to be slightly more developed than normal for his age at the time of his disappearance. However, each of these observations was explained by normal aspects of the decomposition process. Much of this speculation originated during interviews with Domaszewicz's mother, in defence of her son's innocence.

Criminal matters Arrest of Domaszewicz On 16 July 1997 Domaszewicz was arrested and charged with the murder of Leskie. As Leskie's body was not yet discovered, the case against Domaszewicz was mainly circumstantial. Police alleged that Leskie died sometime during a six-hour period of non-contact, from the time he entered Domaszewicz's house and before Murphy left the hotel. Police alleged that after Domaszewicz killed Leskie, possibly by accident, Domaszewicz walked his body into the dam. This theory was supported by police searches of Domaszewicz's home, which uncovered his wet wallet, as well as wet money hidden under a mattress—police alleged these items to be consistent with being submerged in water. Several tissues stained with Leskie's blood were also discovered in Domaszewicz's household rubbish; however, it was not considered to be a significant amount of blood.

Domaszewicz immediately rejected that he killed Leskie, instead claiming police were engaging in harassment and had falsely accused him of murder, referring to his accusers as 'dogs' in the media. These claims of police harassment were later repeated by Domaszewicz's defence lawyer, alongside allegations of illegal interview recordings, contradictory witness statements, and a lack of tangible evidence presented by police.

Trial Domaszewicz was charged with Leskie's murder and was tried for the murder or manslaughter of Leskie in the Supreme Court of Victoria. A jury found Domaszewicz not guilty on 4 December 1998. During the trial, several witnesses testified that he had engaged in prior acts of aggression and violence toward Leskie, such as hitting him across the face, pushing him aggressively, and locking Leskie in dark rooms when he felt annoyed by the child.

Coronial inquiries In December 1998, following the acquittal of Domaszewicz, the State Coroner, Graeme Johnstone, was petitioned to open an inquest into Leskie's death. After commencing an investigation, in January 2002 the Deputy State Coroner advised that he would not hold an inquest, under his discretionary powers. However, he did release a record of his investigations into Leskie's death. Following further petitions in June 2002, Coroner Johnstone reopened the matter and, on 26 September 2003, set aside the findings by his Deputy, and ordered an inquest, that commenced on 17 November 2023. Domaszewicz's lawyer made an application to the Supreme Court for the inquest to be stayed; and it was partially granted on procedural grounds. A new inquest commenced on 11 July 2005. Domaszewicz was not required to testify and the evidence heard at the earlier inquest was adopted for the fresh inquest. On 31 July 2006, Coroner Johnstone found that Domaszewicz had contributed to the toddler's death and had likely disposed of the child's body. However, Johnstone stopped short of finding Domaszewicz solely responsible for Leskie's death, citing lack of evidence. The Coroner's findings were the closest the case came to a resolution.

Aftermath