ADELAIDE'S controversial street preachers are taking their hate messages aboard city trains.

The preachers came to blows with drinkers this week after shouting their message to patrons at a Victor Harbor hotel.

And now they want police to fine them for their behaviour on trains so they can challenge free speech laws in court.

Members of Street Church Adelaide have polarised the community in recent years with vocal Friday night protests in Rundle Mall in which they shout slogans at passing shoppers such as "you are all sinners and will be killed by God".

Preachers spokesman Caleb Corneloup said the group had been taking their message aboard city trains over the past fortnight in an effort to spread their word further.

A spokeswoman for the Department of Transport said police had been called to remove preachers from trains on the Noarlunga line in two separate incidents on December 21.

Transit staff reported that two male preachers were "abusing" passengers with slogans such as "homosexuals are sinners and women are all sinners" while the third recorded the incident on a mobile phone.

Police met the train as it arrived at Adelaide railway station and the preachers left the train.

"Preaching on public transport is of concern to the Department, as it would be likely to cause discomfort for customers on board and in prescribed areas such as stations," the spokeswoman said.

"In the event of such an incident, the Department will consider the options available under the Passenger Transport Act."

The spokeswoman said fines could be issued by either police or Passenger Service Assistants.

Mr Corneloup said no fines had been imposed as yet, but he was eager for police to issue a member with an expiation notice so they could challenge the laws in a criminal court.

"I think if a police officer issues a fine that is the best way to do it, so that we can test the laws in front of a magistrate," he said.

Mr Corneloup denied preachers were hassling commuters and claimed their methods aboard trains were conducted in a "more gentlemanly" way than the Rundle Mall gatherings.

"It is a really good environment for preaching," Mr Corneloup said. "You have got a captive audience and it is much easier to get your message across. You are able to preach in a lower voice."

The preachers challenged a ruling by Adelaide City Council that the gatherings were unlawful.

In August, the Full Court of the Supreme Court ruled they had a right to continue their controversial sermons.

Mr Corneloup said the previous court ruling gave him confidence his group had every right to preach on public transport.

Public transport regulations stipulate people cannot act in a manner that "is likely to interfere with the comfort of, or disturb or annoy, another person".

"Let's say you had a really smelly guy come on the train," Mr Corneloup said. "His presence could be annoying or interfering with someone else's comfort but does the law extend to that? I don't think so."

While the group's Rundle Mall preaching has sparked clashes between group members and pro-gay rights protesters, Mr Corneloup said few people had objected to their presence on trains.

"Almost everyone just sits and listens," he said. "One or two people out of the blue might say they don't want to hear about religion but there have been no real problems."

People for Public Transport SA spokeswoman Margaret Dingle said while the organisation had no formal policy about preaching on trains, she was concerned commuters may be unnecessarily bothered.

"It is a difficult issue because people have the right to put their point of views across, but they should not do it in such a way that bothers other passengers," Ms Dingle said.