The dean of the faculty of advocates has criticised Scottish Green MSP Maggie Chapman for what he described as “reprehensible” comments attacking the judiciary following the Supreme Court judgement on the definition of a woman.

Ms Chapman – the deputy convener of Holyrood’s Equalities committee – was filmed at a weekend rally condemning what she called “bigotry, prejudice and hatred coming from the Supreme Court”.

In a letter to the committee, Roddy Dunlop KC called the remarks “outrageous” and said they created a “risk of danger” to members of the Supreme Court.

Chapman said she stands by her comments, and that it was her role to “stand up and represent trans people”.

The Scottish government is to make a statement in Holyrood on Tuesday afternoon setting out its response to the unanimous ruling that a woman is defined by biological sex under equalities law.

Protests were held at the weekend by pro-trans campaigners, with First Minister John Swinney saying he understood why the trans community would feel “uncertain and anxious” over the ruling.

Chapman – a long time supporter of trans rights – attended a protest in Aberdeen and told the crowd: “We say not in our name to the bigotry, prejudice and hatred that we see coming from the Supreme Court and from so many other institutions in our society.”

Roddy Dunlop KC said the comments were “beyond the pale” and that Chapman should consider her role as deputy convenor as her remarks conflicted with Scottish Parliament guidance on impartiality.

He said her comments “fail to respect the rule of law” and “constitute an egregious breach of Ms Chapman’s duties to uphold the continued independence of the judiciary”.

He added: “But they go further than that, and create a risk of danger to the members of the court themselves.

“This behaviour is irresponsible and reprehensible.”

He added that he expected a “swift and fulsome” apology from the MSP.

Alba MSP Ash Regan said she had reported Chapman to the Presiding Officer and Standards Committee, adding: “MSPs have a duty to uphold the law, not undermine it.”

Speaking on Tuesday morning, Chapman said she would not apologise, and that institutions and laws reflected transphobia and prejudice present in society.

She also said the rule of law “still stands”, but that it was her role to “stand up and represent trans people”.

Last Wednesday’s ruling was the culmination of a long-running legal dispute between the Scottish government and campaign group For Women Scotland over whether sex-based protections should only apply to people born female.

The Scottish government’s social justice secretary Shirley-Anne Somerville will outline to Holyrood implications of the ruling and the processes that will follow, including ensuring updated guidance is issued for public bodies on access to single-sex spaces such as female toilets and changing rooms.

Deputy First Minister Kate Forbes, who was opposed to Scottish government plans to make it easier for trans people to be granted a gender recognition certificate, told BBC Scotland News she did not feel vindicated by the court ruling but that it had provided “legal clarity”.

Trans campaigners have expressed concern the ruling would erase protections they have against discrimination in their reassigned gender.

The Holyrood statement comes as Bridget Philipson, the UK government’s equalities minister, told the BBC’s Today programme that trans women should now use toilets according to their biological sex.

But she stopped short of explicitly saying trans women should use the men’s toilets.

She also said that further guidance by the Equalities and Human Rights Commission would be issued, including a statutory code of practice.

Philipson said this would ensure “everyone has the ability to access services that are safe and appropriate”.

Meanwhile, Prime Minister Sir Keir Starmer welcomed the ruling in his first comments on the matter, saying it gave “much needed clarity”.

The Scottish government argued in court that transgender people with a gender recognition certificate (GRC) are entitled to the same sex-based protections as biological women under the Equality Act 2010.

The judges unanimously ruled that the terms woman and sex in the 2010 Equality Act “refer to a biological woman and biological sex” rather than “certificated sex”.

Michael Foran, a lecturer in law at the University of Glasgow, told the BBC the decision “has profound implications for trans inclusion in those spaces”.

He added debate surrounding the ruling had been muddied by misinformation and “attempts to delegitimise” the Supreme Court.

He added: “It’s incumbent on the government to communicate clearly what this judgement does and does not say, and to combat that misinformation.”