The prosecution of the parents of a young Muslim convert dubbed Jihadi Jack has been described as inhumane to the point of being cruel, a court heard.
Organic wheat farmer John Letts, 58, and his former Oxfam fundraiser wife Sally Lane, 56, are on trial at the Old Bailey accused of funding terrorism.
They allegedly sent or attempted to send £1,723 to their son Jack Letts after he travelled to Syria in 2014 aged 18 and joined Islamic State.
Jurors have to decide whether a person would reasonably have suspected the money would go to terrorism and whether the couple acted under duress believing their son was in immediate danger at the time.
The couple deny three counts of funding terrorism and are standing trial at Londons Old Bailey.
Mr Letts defence counsel, Henry Blaxland QC, said the parents from Oxford were supportive of the battle against terrorism.
In his summing up, he said: But this prosecution does absolutely nothing to further the prevention of terrorism.
In fact it runs the risk of undermining the fight against terrorism because it runs the risk of bringing the law into disrepute.
This prosecution is completely inhumane to the point of being cruel. These parents have to all intents and purposes lost their son.
They are having to deal with that. They are having to deal with the trauma.
Mr Blaxland added that the couple had been let down by the authorities and been given contradictory advice by the people they turned to for help.
Earlier, Mrs Lanes counsel Tim Maloney QC said an email sent in December 2015 by a police family liaison officer said Mr Letts had been informed they can send Jack funds if there is a genuine belief he needs assistance to leave Syria.
The note added the couple needed to capture all their communication with Jack and remain open with the police.
Mr Maloney added: How is that not permission?
The court heard that follow-up advice three days later said any decision to send money rests with them and they could be liable for prosecution.
The QC added this advice was not clear and unequivocal.
On Wednesday, prosecutor Alison Morgan QC told jurors: Parents turning a blind eye to the obvious is not a defence.