This is the proposal:
Adding an 8th Principle of “Respect” to the Seven Principles of Public Life reflected in the Code of Conduct, to abide by the Parliamentary Behaviour Code and demonstrate anti-discriminatory attitudes and behaviours through the promotion of anti-racism, inclusion and diversity.
The seventh principle already requires respect, in a general "we know it when we see it" way. So why do they need an extra principle? The suggested addition requires MPs to demonstrate a specific ideological position. Anyone questioning it could, by doing so, put themselves in breach of the rules. It would become impossible to deny systemic racism, for example, if your model of society saw racism as a matter of individual attitudes rather than a collective social feature. It would be positively un-inclusive to claim that women are adult human females.
To pre-empt an obvious reply, yes, most certainly it is a specific ideological position, for at least two reasons. First, the packaging together of anti-racism, inclusion and diversity as the important "anti-discriminatory attitudes and behaviours" while ignoring sexism, misogyny, religious sectarianism and so on is an emphasis which clearly shows what the drafters think is important. Second, it ignores the fact that sometimes there are reasons to exclude people and restrict diversity. The whole area of safeguarding depends on it.
So maybe it can be rephrased. Something more general. Something which doesn't try to define acceptable content. Something like "Holders of public office should exhibit these principles in their own behaviour and treat others with respect."
Which is what it already says in principle number 7.