Key Muslim leaders in Sydney have appealed directly to the man most likely to become the next NSW police commissioner, asking him to back away from enforcing "draconian" laws that make it a crime to support the civil war in Syria.

Current Deputy Police Commissioner Nick Kaldas was asked to convey that stark message not only to his colleagues in law enforcement agencies, but to politicians in the federal arena too.

The law in question is the Foreign Incursions Act, which makes it a crime to support the war in Syria by going over to fight, or by providing material and financial support to warring parties.

Three people have been charged under the law but so far none are far enough through the judicial process to test the strength of the evidence.

Muslim community leaders, including Dr Jamal Rifi - one of the figureheads in the Syrian diaspora who attended the closed meeting with Deputy Commissioner Kaldas - say the crackdown has killed kindness too, as donations to help civilian causes in Syria have all but dried up.

"In the last six months since the Government highlighted these draconian laws, we have seen a drying out of all community activities to support the Syrian refugees", he said.

"The Syrian revolution is in its fourth year. Whoever wanted to go and fight has already gone."

Government response to the Syrian conflict

The law and order push against supporting the fighting in Syria gained real momentum after the election of the Abbott Government last September.

After the interventionist approach touted by former prime minister Kevin Rudd, Tony Abbott as PM is a study in contrast.

Mr Abbott made an infamous assessment of the Syrian civil war during the election campaign, saying "it often seems like a struggle that involves baddies versus baddies".

Dr Rifi says the remark angers him, and it is hugely insensitive to those involved in the conflict.

"Ordinary citizens have suffered; hundreds of thousands of people have died. There are millions that have been displaced inside the country and outside the country. How can he claim [this is a fight] between two baddies?" he said.

"No. There are a lot of goodies.

"Syrian people wanted to have their freedom. [President Bashar al-] Assad was killing everyone. How can he equate between the two? He had no right whatsoever."

Muslim leaders question evidence of Australian fighters in Syria

Rights are at the heart of Muslim concerns regarding the enforcement of the Foreign Incursions Act.

Many see the act as a law that seeks to limit freedom of movement.

The right to free expression is a luxury item that Muslim leaders like Dr Rifi see as an ironic paradox.

Dr Rifi says the more he speaks out, the more likely he is to attract ridicule and the unwarranted suspicion of any number of state or federal agencies of law.

Dr Ibrahim Abu Mohamed, the Grant Mufti of Australia, has been in closed meetings with the NSW Deputy Police Commissioner. ( YouTube: MEMRITVVideos )

He says has received calls from federal agencies on a regular basis.

"I quite like chatting to ASIO and the Federal Police," he said.

Dr Rifi refutes the claim that Australia, per capita, supplies some of the highest number of foreign fighters to the conflict.

"What is their evidence?" he said.

"So far in the media we've only heard of a handful of Australians who are engaged in the fighting in Syria. Now I know it is going to be very hard to have any evidence. But we haven't seen it."

Federal Attorney-General Senator George Brandis says he has evidence, but has not been very specific.

In a response to Dr Rifi's comments, the Attorney-General pointed to "intelligence" that showed "money is being raised within the Islamic community for ostensibly humanitarian objectives which is being used for the purposes of terrorist financing".

Pointing to that being a breach of Australian law, the statement advised "those who want to support humanitarian relief in Syria to do so by donating to appeals being conducted to reputable aid agencies."

A NSW Police spokesperson would not provide a detailed response on whether they had evidence of Australian fighters being sent to Syria.

"We only target those who are suspected of committing criminal offences," the spokesperson said.

The highest official of Muslim religious law in Australia, Grand Mufti Ibrahim Abu Mohamed, hosted the closed meeting with Deputy Commissioner Kaldas, but has maintained his usual silence on the matter

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