Dezi Freeman's devices contained hundreds of files of child abuse material when police attempted to execute a search warrant at his home in August.
Freeman, 56, spent months on the run after he murdered two police officers that day, who had been attempting to serve him a warrant over historic sex crime allegations.
The so‑called sovereign citizen was shot dead on March 30 by heavily armed officers during a siege at an off‑grid compound in Victoria's northeast, following a lengthy police operation to find him.
After the fatal search warrant last year, in which police had been instructed to seize Freeman's devices, hundreds of files containing child abuse material were later found, the ABC reports.
Multiple law enforcement sources have since told the national broadcaster that the police investigation into historical sex offences included allegations of sexual exposure, with detectives in contact with one alleged victim.
However, Freeman will never face charges following his fatal shootout with police.
Officers located him inside a converted shipping container, or a 'long caravan,' as they called it, at Tholo Farm near Walwa, 188km northeast of Porepunkah, where he had fled the previous year.
Footage showed him wrapped in a blanket when he emerged from the shipping container, which appeared to be a makeshift campsite, before pulling a gun from underneath and pointing it at police. He was hit by up to 27 bullets.
Hundreds of files of child abuse material have been found on Dezi Freeman's devices
The devices were seized after the fatal search warrant in August last year when Freeman killed two police officers and fled into the bush
There had been no sign of him until a Thologolong local reportedly spotted him at the camp near the Victoria-New South Wales border and alerted police.
Questions have also circulated about who alerted police to where Freeman was holed up, particularly after a $1million reward was offered for any information leading to his arrest.
Victoria Police Chief Commissioner Mike Bush stated at any details would remain confidential and declined to address questions suggesting a tip-off had prompted the operation.
There have been reports, including from the Herald, that a car travelled several times to and from the Porepunkah area, possibly prompting police investigations there.
Other communications from the fugitive in the days and hours after he shot two police officers have also come to light, as more scrutiny is placed on the seven-month manhunt.
Hours after fleeing the tragic scene, Freeman reportedly sent a text message to his wife, Mali, saying, 'see you in heaven'.
This initially helped detectives establish a search area of about 10km to 15km from the couple's home in Porepunkah.
He then made a call to an associate a few days later saying he 'F***ed up', but police were unable to determine his location, even after intercepting the call.