The Christian Institute is threatening legal action against the Scottish Parliament if it moves ahead with a proposed ban on conversion therapy.
It comes as the Scottish Parliament's Human Rights Committee has issued a report urging the government for a "swift and comprehensive" legislation.
Last year, the Scottish Government committed to bring forward “legislation that is as comprehensive as possible within devolved powers by the end of 2023, if UK Government proposals do not go far enough”.
The proposed ban would outlaw practices that seek to change someone's sexual orientation or gender identity.
But The Christian Institute (CI) is accusing the Committee of “bias” as its members had previously signed the End Conversion Therapy Scotland (ECTS) campaign, a public petition first lodged in August 2020.
“You can't say that you're scrutinising legislation properly, if seven out of the ten people tasked with doing it have already said: ‘We only see one answer to this’,” Ciaran Kelly, deputy director at CI told Premier.
“So we've just simply warned the Scottish Government, that if you pursue putting through a law without doing it properly, then you leave yourself wide open to legal action, and we will take that legal action.”
CI and other Christian groups are concerned the current broadly worded ban would criminalise the ordinary work of churches, such as praying for someone with unwanted same-sex attraction.
Some of the legislation reads: “Conversion therapy is an umbrella term for a therapeutic approach, or any model or individual viewpoint that demonstrates an assumption that any sexual orientation or gender identity is inherently preferable to any other, and which attempts to bring about a change of sexual orientation or gender identity or seeks to suppress an individual’s expression of sexual orientation or gender identity on that basis.”
In a letter to Holyrood's presiding officer Alison Johnstone, CI said: “The public expects impartial scrutiny. Instead, Committee members have made promises to campaign groups and taken evidence disproportionately from those supporting the petition.”
It continued: “The Christian Institute was involved in the successful legal challenge to the Named Person legislation where Parliament failed to properly scrutinise proposals. Inadequate scrutiny by Parliament in this case may again result in human rights challenges being brought against any resulting legislation.”
A Scottish Parliament spokesman said: “Any correspondence received by the Presiding Officer will be given proper consideration and responded to accordingly.”