A plasterer from Edinburgh is facing up to a year in jail in the United Arab Emirates for allegedly possessing counterfeit money.
William Barclay was stopped at Dubai International Airport in September in connection with an incident at a shopping mall in the country in 2016.
He was questioned by police for three days then released on bail, but his passport has been confiscated.
The Foreign Office said it was providing assistance.
Mr Barclay was quizzed by detectives for 12 hours after trying to exchange money at the Al Hamra Mall in Ras Al Khaimah in 2016.
He was accused of being in possession of counterfeit cash but then told no charges would be brought and was allowed to continue his family holiday.
On returning to Dubai on 15 September this year, with his wife Monique and two children, Mr Barclay was stopped at the airport.
He has since been released but his passport has been confiscated as he must remain in the country until the case is concluded
Mr Barclay could face up to a year in jail in the UAE, a £1,000 fine and deportation back to the UK. His family have returned to their home in Edinburgh without him.
Radha Stirling, chief executive of British non-governmental organisation Detained In Dubai, which is representing the family said: "Clearly in this case, Mr Barclay received a counterfeit note that was already in circulation and is himself a victim.
"Charging him over a fake note he received and passed unknowingly is not an effective way to deal with the problem of counterfeiting and it once again highlights the risks visitors to the UAE face from the country's legal system.
"He was detained for three days, moved from one facility to another in shackles, and though he is now out on bail, his passport has been confiscated and he is stuck in the UAE indefinitely.
"We hope that the charges will ultimately be dropped, but in the meantime, Mr Barclay is in a very difficult situation."