Lawyers acting for Miguel Hayworth, 29, have demanded an explanation over the alleged intimidation and abuse of power by three officers.
Andrea Minichiello Williams, the director of the Christian Legal Centre, has written to Peter Fahy, the Chief Constable of Greater Manchester, over the incident.
She claims that Mr Hayworth and his father, John, 55, were unlawfully and unfairly treated as they preached Christianity in the city at the end of July.
"They were clearly told that reading the Bible and preaching can be offensive and that they could be arrested," she wrote.
"Furthermore, they were subjected to abuse and intimidation. They were told that they were being monitored and filmed," she wrote.
Critics claimed that a Muslim preaching his religion in the street would not have been treated in such a way by police.
Mr Hayworth, a voluntary worker who is married with two children, has been a street preacher in the Manchester area for five years and he is often accompanied by his father.
He said that he and his father had decided to preach from 11am at St Ann's Square in Manchester instead of their usual place on nearby Market Street.
He was reading passages from the Old and New Testaments while his father distributed leaflets containing the message of the gospel.
"At 2pm, I was approached on more than one occasion by several police officers who falsely accused me, stating that I was inciting hatred with homophobic and racial comments," he said.
"One plain-clothed officer, who was with the other two uniformed officers, said: 'It is against the law to preach and hand out tracts: preaching causes offence and handing out tracts is harassment and could result in an arrest.'"
Mr Hayworth said that at about 2.30pm a second officer confirmed that his colleague had accused the preacher of inciting religious and racial hatred and wanted to warn him that this was an arrestable offence.
The second officer, Mr Hayworth claimed, also warned him his actions were being videoed and recorded, and he stopped preaching.
Some passages in the Bible are regarded as homophobic. For example, sections read out by Mr Hayworth in St Ann's Square included Romans Chapter 1 Verse 27, from the King James Bible, which says: "And likewise also the men, leaving the natural use of the woman, burned in their lust one toward another; men with men working that which is unseemly..."
He also read from 1 Corinthians Chapter 6, Verse 9: "Know ye not that the unrighteous shall not inherit the kingdom of God? Be not deceived: neither fornicators, nor idolaters, nor adulterers, nor effeminate, nor abusers of themselves with mankind."
Mr Hayworth says he cannot understand how the racism complaint arose. Shortly after being confronted by the police, he stopped reading from the Bible.
He and his father later approached the Christian Legal Centre, which seeks to promote religious freedom and, particularly, to protect Christians and Christianity.
The centre, in turn, has instructed Paul Diamond, the leading religious rights barrister.
The centre and Mr Diamond believe that the police abused their powers during the dispute on Saturday, July 25.
It is against the law to use offensive, threatening or abusive words or behaviour. It is also an offence to incite hatred on grounds of race, religion or sexual orientation.
However, in its letter to the police, the Christian Legal Centre said: "Freedom of religious and freedom of religious speech is specifically protected by the European Convention on Human Rights."
The letter added: "This means that any restriction on the 'right' to evangelise will have to be justified by the Police by a 'pressing social need'.
"In a free society, this is very difficult to do; and a few complaints by irate individuals will not suffice."
The centre and Mr Diamond have represented a number of Christians in alleged religious discrimination cases.
Earlier this year The Sunday Telegraph revealed that Caroline Petrie, a nurse, has been suspended from her job for offering to pray for an elderly patient's recovery from illness. She was later reinstated.
Chief Inspector Chris Hill, of Greater Manchester Police, said: "Police were called to St Ann's Square in Manchester city centre following complaints from members of the public who considered the comments being made by two street preachers as racist and homophobic.
"When spoken to, the men said they were quoting from the Bible. The officers confirmed they were entitled to preach on the street, but advised them offensive behaviour is not acceptable.
"No one was arrested. I have received a letter from the Christian Legal Centre and will respond in due course." (Daily Telegraph, 8.15.2009, Andrew Alderson) http://www.telegraph.co.uk/news/newstopics/religion/6034144/Preacher-threatened-with-arrest-for-reading-out-extracts-from-the-Bible-in-public.html
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