The mayor of Greater Manchester, Andy Burnham, has accused the Premier League of an abuse of process in its attempt to impose a 10-point penalty on Everton and said the club’s punishment must be declared null and void.

“The fact that the Premier League sought to introduce a new sanctions policy in the middle of this process amounts, in my view, to an abuse of process,” wrote Burnham, who has also requested any evidence that the Premier League discussed Everton’s case in relation to the proposed introduction of an independent regulator. “From my experience of regulation, introducing new rules in the late stages of a process would be regarded as regulatory malpractice.”

Burnham explained the reasoning behind his letter at Goodison Park, where he was attending Everton’s home game against Manchester United on Sunday. He said: “The first thing I want to say is that I am not saying Everton Football Club does not have a case to answer. Clearly it does have a case to answer. But in some ways that is not the question.

“The question in this situation is, has there been a fair process? Having taken my time to study the judgment and speak to a lot of people this week I have concluded that there has not been a fair process. There has been a highly flawed process and I would go as far to say there has been an abuse of process. And that abuse of process concerns the guideline and framework that was put together in August and submitted to the independent commission.

“You cannot, in an ongoing case, create new policy in the middle of the case and then introduce it towards the end of it. It is what people would call regulatory malpractice. You end up with a situation here where a harsh penalty has been handed out, which is what the Premier League wanted, where there is no policy basis for that penalty.

“Therefore, how can an appeal be anything other than an arbitrary process as well given there is no policy basis? As far as I can see the process is null and void. It has been invalidated by the actions of the Premier League in seeking to introduce a framework at the later stages of the process and it would appear to have had some impact on the independent commission.”

Burnham believes the Premier League’s motives for wanting a heavy penalty for Everton – clubs who go into administration are docked nine points – is the threat of the government introducing a new independent regulator for football. He added: “There is no way Everton can get justice within this process, and a fair hearing. It is my opinion, I am pretty certain, that a linkage was made between the concern about an independent regulator and Everton’s case.

“I think the decision to move it forward in the way it was done, without those PSR sanctions in place, reflects a will to be seen to be doing something. I’ve asked the chair of the Premier League whether there were any conversations within the Premier League linking the two matters. It’s widely believed that is what is happening in this situation and it simply is not right for this football club to be used as a pawn in that situation.”