A 23-year-old west Belfast man is taking legal action against Iris Robinson over her controversial comments on homosexuality.
Robert Toner from Poleglass has also written to the Equality Commission asking them to back his complaint over the first lady's anti-gay remarks.
Last week Mrs Robinson, a DUP MP, MLA and chair of the Assembly's Health Committee, sparked outrage when she described homosexuality as an " abomination" and said gays needed psychiatric help to be "turned around".
Mr Toner, who came out five years ago, believes his human rights have been breached. He has lodged a formal complaint with police and enlisted the help of solicitor Kevin Winters to pursue a legal challenge.
Mr Toner, a gay rights activist who has suffered homophobic abuse, said he was "worried" about the effect Mrs Robinson's comments could have on the wider community.
Last night he told the Belfast Telegraph: "It is very, very hurtful to think that someone says I need psychiatric help because I am gay. It is totally uncalled for, it is totally horrendous that a public representative has said this.
"I have done two things. Firstly, I have made a submission to the Equality Commission — I have sent a letter asking them to back our complaint. And my solicitor is also looking into a possible breach of the Public Order Act — article 9 — which deals with threatening behaviour and insulting words.
"She condemned the gay-bashing attack on a man in Newtownabbey, but then used the attack on him as a tactic to browbeat homosexuality — I find that very worrying.
"I come from west Belfast where the number of suicides is very high — a number of those suicides could be because of issues with sexuality."
In 2005 Mr Toner successfully challenged Lisburn City Council after it banned same sex marriages from the civic centre wedding room.
"The majority of members of the gay community have been very welcoming to the fact I am taking legal action. And the heterosexual community welcomed it too. Most people agree that something needs to be done about Iris. I am confident that with the support of the Equality Commission we are going to win this.
"I am quite happy to take Iris on in the fight."
Yesterday it emerged that hundreds of people have signed a petition calling for the Prime Minister to reprimand Mrs Robinson. The online petition, open until August 9, will be delivered to Gordon Brown at Downing Street.