But while the men said they felt vindicated by the decision, which found their silent prayers were not a protest, the clinic's spokeswoman expressed disappointment, saying women in 2018 should be able to access the medical procedure "without having to be judged by three men with rosary beads".

Anti-abortionists Kerry Mellor, 76, John Popplewell, 76, and Ken Clancy, 79, had for years been part of a pro-life group that gathered outside the abortion clinic in the ACT Health building on Moore Street on Fridays.

The group would sometimes bring props, such as an image of the Virgin Mary, a crucifix and a box with a model of an unborn fetus.

In 2016, the territory government, seeking to protect women who were attending the clinic for medical appointments, introduced an exclusion zone and banned protest within it.

The prayer group stopped gathering together at the site once the new laws were introduced. However, some members continued to go to the site on Friday mornings, now without most of the props. They did not stand in a group, and said they only engaged in silent prayer alone.

On February 3 last year, Mr Mellor, Mr Popplewell and Mr Clancy were fined $750 for protesting in the exclusion zone. But the three refused to pay their fines and were summonsed to face court. They pleaded not guilty to the charge of engaging in protest in a protected place and faced a hearing in the ACT Magistrates Court over their actions that day.

In a video tendered to court, the men are shown walking past the clinic, alone and without speaking to anyone, save for brief acknowledgements of each another. One man sits alone on a bench outside the clinic holding rosary beads.

Prosecutors argued that the men's conduct amounted to public protest, given their history of opposing abortion at public prayer vigils. But their defence questioned how walking around silently praying could amount to protest.

Magistrate Glenn Theakston found for the defence, and that the protesters were not involved in a "protest, by any means".

He said two features stood out.

"There is the presence of the normal and the absence of the abnormal," he said of the men's behaviour that day. "They simply do not stand out as participating in any extraordinary activity. They do not even gather. I make these observations cognisant of their previous involvement in prayer vigils and their admitted views about abortion.

"I accept they were each engaged in silent prayer, and that such prayer involved no component of expression, communication or message to those around them."

Mr Clancy was not well enough to attend on Friday, but Mr Mellor and Mr Popplewell, speaking outside court after the decision, said that they had always believed what they were doing was not protest.

Mr Mellor said they opposed Canberra's laws on abortion and would continue to silently pray at the clinic.

"We were doing nothing that would single us out from any other person in the street, everybody's entitled to their personal prayers," Mr Popplewell said. "As his Honour said, the case was not proven."

Acting chief executive of Marie Stopes Australia, Jacquie O'Brien, said staff were disappointed by Friday's result.

"While the presence of prayer vigils may seem harmless to many, we do see their negative influence on patients in places where safe access zones are not in place," she told The Canberra Times.

"Patients can often feel judged and scrutinised as a result of their presence. The fact is that in 2018, women really should be able to access this common medical procedure without having to be judged by three men with rosary beads."

The case will return to court later this month to determine the question of costs.