A man on trial for alleged historical child sex abuse - some of which he is accused of perpetrating with his identical twin brother - repeatedly assaulted two teenage boys over several years, a court has heard.
Stephen Mateer allegedly raped and sexually touched the boys he met through a Lake Macquarie pizza shop while they were aged between 12 and 15 years old - from 1989 to 1993, Crown prosecutor Brendan Queenan said on Monday.
Mr Mateer, 70, was earlier this month deemed unfit to stand trial over 45 abuse counts due to impaired cognitive ability believed to be dementia, so is the subject of a special hearing in Newcastle District Court.
The hearing is being run concurrently with the judge-alone trial of his twin Richard Mateer, charged with one count of rape and six charges of assaulting and committing an act of indecency against one of the alleged victims - a 13-year-old - in the company of his brother.
Stephen and Richard Mateer were arrested after detectives from Strike Force Arapaima - investigating the long-unsolved disappearances of Lake Macquarie girls Robyn Hickie and Amanda Robinson - were tipped off to a string of alleged sexual assaults against two boys in the late 1980s and early 1990s.
In his opening address, Mr Queenan said it would be alleged that the attack involving both Mateers took place in the back on a van.
He said the brothers allegedly touched the child on the genitals before telling him to remove his pants - then going on with an alleged ordeal that involved the boy being incited to manually stimulate each of the men before Richard Mateer raped the teenager.
The acts Stephen Mateer is accused of committing on his own include allegedly inciting two teenagers to participate in sexual activity with each other while he watched and sexually stimulated himself.
He also allegedly assaulted both boys on separate occasions while taking them for driving lessons, the court heard.
The special hearing and trial continues today.
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