Australian filmmaker James Ricketson on Thursday hit out at having lost 15 months of his liberty in pre-trial detention on a charge supported by “little evidence”.

It was the third day of his trial on espionage charges.

No witnesses were called on Thursday as those expected to testify were family members of Ricketson’s stepdaughter, who were attending to her after she gave birth on Wednesday night.

Ricketson is charged under Article 446 of the Criminal Code with “acts of collecting information that may undermine national defence”. He faces up to 10 years in prison if found guilty.

He was arrested in June last year while flying a drone to capture images of a rally by the court-dissolved Cambodia National Rescue Party on the final day of commune election campaigning.

Ricketson spent the morning session answering questions on his professional career from prosecutor Sieng Sok, with the 69-year-old eventually asking the court why there had been no discussion of his espionage charge.

“I was arrested and put in Prey Sar for 15 months, and I don’t [even] know which country I [was supposed to be] spying for,” he said and asked for evidence to support the charge.

Presiding Judge Seng Leang said Ricketson would know before long as proceedings were soon to be completed.

“This is a trial, and it takes place over Thursday and Friday and will be completed soon. You will then know,” he said.

Earlier in the day, Ricketson said he had worked as a filmmaker for 45 years. He first came to Cambodia in 1996 to start working on a 55-minute film Sleeping with Cambodia for ABC Australia and the Australia Film Commission.

He said the documentary concerned child prostitution, street kids and those who had lost their land.

“It was very critical of NGOs that I believed were exploiting the poor. There is no political comment at all in the film,” he told the judges."

Ricketson said in 2007 he produced a film for Al Jazeera and he was producing three more unfinished films including the life of Chanthy, his goddaughter, who escaped life as a beggar with his help.

Ricketson said he had worked in 20 different countries, including Cambodia.

Sok asked whether Ricketson had permission from the authorities to produce the films.

Ricketson said he had received permission from the Ministry of Information to work in the Kingdom.

In the afternoon session, the prosecutor questioned him on two emails – one sent in November 2015 to a friend and lawyer in Australia, and another that was sent to the then CNRP president Sam Rainsy.

“Your email said: ‘Hun Sen has guns, tanks, water cannons and over 10,000 bodyguards.’ Where did you get this information from? And what was the purpose of sending this information?” the prosecutor asked.

Ricketson said that, as a journalist, he had journalist friends who talked about such things. “If this information was not correct, just say I am a bad journalist,” he replied.

On August 18, 2013, Ricketson sent an email to Rainsy asking about an arrest warrant. Ricketson said the email was merely sent in a professional capacity as a journalist.

He said he first met Rainsy in 1997 during registration for the national elections. That same year, he also interviewed dual prime ministers Hun Sen and Prince Norodom Rannaridh.

As a journalist, he said that he had met Sam Rainsy many times at the CNRP head office as he was then the president of the party, but that Ricketson was not involved with the CNRP.

The prosecutor then showed photos taken by Ricketson that were found in confiscated cameras. They showed police preparing to crack down on protesters at Freedom Park. The prosecutor asked why he took the pictures and who he intended to send them to.

“Such pictures had been taken by other journalists – this is a journalist’s job,” Ricketson replied. “I would like to ask Mr Sieng Sok: are these pictures why you have put me in jail for 15 months?”

Kong Sam Onn, Ricketson’s defence lawyer, requested the judges to immediately decide on the case, saying there was no more evidence to come from the prosecutor and so no need to further burden his client.

“As the lawyer for the defence, I don’t see any more evidence against my client. The court can rule now that my client is innocent.

But the presiding judge denied the request and adjourned the court. The trial is due to conclude on Friday.