A judge facing a disciplinary hearing has complained he is being denied a fair hearing because he has been told he cannot be legally represented or call witnesses.

Judge Peter Herbert, chair of the Society of Black Lawyers, has written to the lord chief justice, Lord Thomas of Cwmgiedd, objecting to the proceedings of the judicial panel, which is due next month to deliberate on remarks he made about racism and the judiciary.

The dispute relates to a speech he made at a rally in Stepney, east London, in April last year. Herbert commented negatively about the decision to bar the former mayor of Tower Hamlets, Lutfur Rahman, from holding public office for five years and claimed that racism was present in parts of the judiciary.

He said in the speech: “Racism is alive and well and living in Tower Hamlets, in Westminster and, yes, sometimes in the judiciary.” His speech is alleged to amount to judicial misconduct because it strayed into commenting about politics, conflicting with his duty to show impartiality.

Herbert says he has been informed that the hearing in July will last only two hours, that he may not be legally represented and cannot call any witnesses. The judge, who sits as a part-time recorder and in immigration and employment tribunals, is separately suing the Ministry of Justice for race discrimination.

In a statement released on Tuesday, Herbert said: “It is simply unacceptable to suggest that a part-time judge, no matter how junior, should be told to resort to an employment tribunal or refer to the judicial conduct ombudsman to seek redress.

“As one of the few judges of African descent in the United Kingdom, who sits in three different jurisdictions, with a consistent record of fighting within the system for justice and equality, to be treated in this manner is a disgrace.

“If this panel are permitted to abridge my right to a fair hearing that sends a very strong message to all members of the African, Caribbean and Asian community that we are simply not equal before the law. I do not expect to be treated above the law that applies to other judges but I do expect to be treated equally.”

His letter to the lord chief justice also complained that the judicial conduct investigations office (JCIO) repeatedly addressed him “without any reference to my OBE”.

Imran Khan, the prominent London solicitor who represented the family of Stephen Lawrence, said: “It is a disgrace that any judge should have his rights to a fair disciplinary hearing limited in this manner. Even an ordinary employee or office holder has the right to call witnesses, in his own defence.

“The intention must be to dismiss his representations without even the fig leaf of impartiality. This is a real slap in the face not just for Herbert OBE but for the right of all our communities to obtain a fair hearing.”

Lady Lawrence. Photograph: Oli Scarff/Getty Images

In a supporting statement, Lady Lawrence, the mother of murdered teenager Stephen, said the case demonstrated that “no matter what your achievements or expertise, your experience is no better than a young black man on the street who is seen as a threat to the justice system simply on account of the colour of their skin”.

A spokesman for the JCIO said: “The JCIO does not comment on cases while they are being investigated. If there is a finding against any judicial office holder, it is published on the JCIO website.”