The parents of a man who joined the group calling itself Islamic State sent him money while he was in Syria, a jury at the Old Bailey has heard.
Jack Letts, who converted to Islam aged 16, travelled to the war zone in 2014.
The court heard John Letts, 58, and Sally Lane, 56, of Chilswell Road, Oxford, sent or tried to send more than £1,700 to their son despite warnings not to.
The couple deny three charges of funding terrorism.
It is alleged that between September 2015 and January 2016 the couple sent or tried to send three payments to Jack, now 23, after he contacted them from the war zone.
‘Sympathy for parents’
Prosecutor Alison Morgan QC told the jury there was no suggestion Jack’s parents were themselves terrorists or supporters of the ideology or actions of the banned IS group.
But she added: “They sent money to their son with knowledge or reasonable cause to suspect that it might be used by him or others to support terrorist activity, or that it might fall into the hands of others who would use it for that purpose.
“It is inevitable that you will have sympathy for them as parents of a man who took himself to Syria against their wishes, but you will also see from the evidence the way in which these defendants came to commit these offences, despite being warned by a wide variety of people.”
The jury heard the evidence would show that the couple knew Jack was in Syria with the IS group and, when he began asking for cash, they suspected he was being manipulated.
Ms Morgan said Mr Letts and Ms Lane were repeatedly told by “numerous police officers” not to send any money.
They received further similar advice from a range of terrorism experts they consulted for help, the court heard.
“It was not open to these defendants to take the law into their own hands, whatever their own reasons and motives,” Ms Morgan said.
“Sending money in such circumstances, where you may conclude that it was highly likely to fall into the wrong hands, is against the law.”
Oxford-based Muslim friends of Jack Letts, who has obsessive compulsive disorder, feared he had been radicalised by extremists, the court was told.
One friend from the local mosque contacted his parents to warn them about that possibility of their son secretly leaving the UK to join the Syrian conflict, and urged them to confiscate his passport.
Despite those concerns, they paid for Jack to fly to Jordan in May 2014, apparently for a study trip, the prosecution said.
The court heard the couple sought to maintain contact with Jack, with Mr Letts messaging his son to talk about his “grand adventure”.
But both parents harboured growing suspicions about Jack’s ultimate motives, Ms Morgan said, and by September 2014 they realised he must have entered Syria.
The trial continues.