Campaigners are demanding the government scrap a clause banning "insulting words and behaviour" from the Public Order Act.
Tory MP David Davis and gay rights campaigner Peter Tatchell have joined forces with secular societies, Christian institutes and civil liberties organisations to campaign for a change in the law under the slogan 'feel free to insult me'.
"It is commendable that David Davis and the Christian Institute are prepared to work with a gay left-wing green atheist secularist like me," Mr Tatchell said.
"We're all putting the right to free speech before our personal politics and beliefs.
"The Section 5 ban on insults is a menace to liberty. It has been abused to variously arrest or threaten with arrest people protesting non-violently against abortion and for gay equality and animal welfare.
"Other victims include Christian street preachers, critics of Scientology and even students making jokes."
Section 5 of the Public Order Act has resulted in many controversial arrests and prosecutions, including several instances in which police officers themselves have complained of being offended by people swearing around them.
Recent guidance has prohibited the police from arresting under Section 5 of the Act when they are the individual being insulted, but campaigners say the vague wording of the law makes it open to abuse by other groups.
Mr Tatchell was arrested under Section 5 in 1994 when he attended a protest against Islamic extremist group Hizb ut-Tahrir with a placard documenting the persecution of gay people.
In 2005 an Oxford student was arrested for jokingly suggesting a police horse was gay.
In 2008, a teenager was given a court summons for holding a placard which branded Scientology a dangerous cult.
In 2010, Christian street preacher Dale McAlpine was arrested for saying gay sex was sinful.
The law does not require that anyone actually feels "harassment, alarm or distress", but merely that the insulting words of behaviour are "likely" to do so.
A recent ComRes poll commissioned by the Reform Section 5 campaign showed 62% of MPs disagreed with any law banning "insults".