UKIP AM Michelle Brown is facing a week’s exclusion from the assembly without pay over a racial slur she used to describe a Labour MP.
Members of the standards committee, including party colleague Gareth Bennett, ruled she committed a “severe breach” of the code of conduct.
Ms Brown made the comment about Chuka Umunna in a private phone call in 2016.
A spokesman for Michelle Brown said she would appeal. She has apologised for any offence caused.
The spokesman, alluding to occasions where Mr Bennett has drawn negative publicity, added: “Michelle Brown is not likely to take any lessons at all on political correctness or conduct, from Gareth Bennett.”
The recommendation of the standards committee, and the results of an investigation by the standards commissioner Sir Roderick Evans that prompted it, have come to light after its report was leaked to BBC Wales.
It will be up to assembly members to decide whether to endorse the exclusion in a vote in Senedd. It is thought to be the first case of its kind.
Ms Brown called the MP for Streatham, Chuka Umunna, a “coconut” in a phone call in May 2016 to her then senior adviser Nigel Williams, which he released a recording of to the Daily Post newspaper last summer.
In his investigation the standards commissioner found that the term “coconut” fell below the standard of conduct required of AMs.
He said the point that Ms Brown was making – that, despite Mr Umunna’s heritage, his privilege upbringing meant he had no greater understanding of the lives of ordinary members of the black and minority ethnic community – was “within the range of points that a politician is entitled to make”.
But he said that fact remained that “Ms Brown, in making her point, resorted to using a term of racial abuse”.
Ms Brown had told the standards commissioner that the comments complained of “were made during a private and personal conversation between two friends and party colleagues.”
But the commissioner said that was “not realistic” as she had been discussing the terms of employment of a person whom she was considering employing.
The committee agreed saying “the term used in this instance was a term of racial abuse, and as such utterly unacceptable”, accusing her of bringing the assembly into disrepute.
It said that the language is “below the expectations of an assembly member and that racism has no place in society”, calling the use of the term a “severe breach” of the code of conduct for AMs which they said applies “at all times”.
According to the report, Ms Brown had argued that the term was “not racist”.
The UKIP North Wales AM told the commissioner that she did not apologise “for using the verbal short-cut coconut”, and that there was no evidence the assembly had been brought into disrepute.
Her words, she said, “were recorded and released to the press without my consent and the motivation for the release was personal spite, not a desire to further the public good”.
However the committee’s report said that she later apologised for any offence her words may have caused, and an advisor to her also accepted that it was a term of racial abuse “at the lowest level of severity”.
Because the Labour group had made the initial complaint only three members of the four member committee – Plaid Cymru’s Llyr Gruffydd, the Conservatives’ Paul Davies and UKIP’s Gareth Bennett – oversaw the deliberations, with Labour AM Jayne Bryant absenting herself.
The committee said it would not expect to see complaints being made by party groups this way again as it has a “detrimental impact on the process”.
It was also concerned that information relating to the complaint by the chair of the Labour group was released to a newspaper at the point of submission to the standards commissioner.
Ms Brown’s spokesman said: “Of course Michelle will be appealing as the committee have reached the wrong conclusion.”
Under the rules, assembly members are given a period of 10 days from receiving a standard’s committee decision to appeal to the presiding officer.
Appeals are only considered on the grounds of significant factual inaccuracies, or procedural irregularities that may have prejudiced the member’s right to a fair hearing.
A UKIP Wales spokesman said: “It would be improper to make a comment on an alleged leaked report.”