Aidan O'Neill KC

The proposals, which he also says are ultra vires, would see faith leaders put behind bars for up to seven years and hit by unlimited fines if convicted of involvement in conversion practices.

The scheme has been condemned in 46-page opinion by Mr O’Neill, who said the plans are “ill-thought out, confused and confusing, and fundamentally illiberal in intent and effect”. 

Mr O’Neill states there are very strong arguments the plans are “beyond the legislative competence of the Scottish Parliament”. Mr O’Neill is advising The Christian Institute (CI), which is opposing the law change that is out for consultation until 2 April.

It was launched last month with an 86-page document proposing a very broad new criminal offence of engaging in a conversion practice.

The proposals garnered a negative reaction from women’s groups who regard it as a form of gender self-ID by the back door, and religious groups who fear vexatious prosecutions targeting traditional teaching on sex and sexuality.

The draft legislation “contains a handful of vague criteria” for what constitutes a conversion practice. It also “allows LGBTQ+ activists” to obtain civil court orders against people they think are responsible for such practices.

Mr O’Neill states: “This is perhaps best described as ‘jellyfish legislation’. The concepts it uses are impossible to grasp; its limits are wholly undefined; it contains a sting in the tail in the form of criminal sanction of up to 7 years and unlimited fines; and thus it will have an undoubted and intended effect of dissuading persons from ever even entering the now murky waters of what may or may not constitute unlawful ‘conversion practices’.”

CI Deputy Director Simon Calvert said: “This is another example of the Scottish government asking Holyrood to exceed its powers and impose draconian legislation on the people. If this deeply flawed law is passed it will be challenged all the way to the Supreme Court if necessary.

“Ordinary mums and dads face criminalisation for trying to extract their kids from the grip of radical trans ideology. Church leaders face prosecution for not praying in accordance with state dogmas. This is outrageous.

“They’ve spent over two years drafting this. It’s time to admit that no-one can define what conversion therapy is, let alone how to criminalise it.”