A Canadian judge who wore a Donald Trump campaign hat into court after the US election has been suspended for 30 days without pay, 10 months after his actions triggered an unprecedented number of formal complaints.

On Tuesday, the Ontario judicial council said the conduct of Justice Bernd Zabel had fallen short of the impartiality and objectivity demanded of judges. “We have no hesitation in finding that Justice Zabel’s actions amounted to a serious breach of the standards of judicial conduct, that it had an adverse impact upon public confidence in the judiciary and the administration of justice,” the council wrote in its decision.

On the day after the US election in November, Zabel entered his courtroom in Hamilton, Ontario, clad in black robes and a red “Make America Great Again” baseball cap. The 69-year-old told those in court that the hat was meant to mark an “unprecedented” night in the United States and singled himself out as the lone Trump supporter among his colleagues.

Days later, amid public anger sparked by media reports of his actions, Zabel apologised for what he called a “misguided attempt to mark a moment in history”. His decision to wear the hat, he said, was not intended as a political statement or to endorse the political views of Trump.

After receiving 81 complaints – 10 times more than the council had received about the conduct of any other judge in the province – the Ontario judicial council said it would hold a disciplinary hearing, with Zabel facing possible removal from the bench.

Many of the complaints highlighted the denigrating remarks Trump had made against women, Muslims and others throughout the election campaign, and questioned whether everyone could expect to be treated fairly and impartially in Zabel’s courtroom.

During the hearing, Zabel told the four-person panel he profoundly regretted his actions, describing them as an “ill-considered, ill-thought out” attempt at humour. “The man depicted in those complaints is not me,” Zabel told the panel. “I’m not a racist, I’m not a bigot, I’m not a misogynist.”

The panel also considered 63 letters and two cards that were written in support of Zabel, many of which praised the 27-year veteran of the bench for his professionalism and integrity.

Pointing to his “unblemished and exemplary service on the bench,” the judicial council said the “single aberrant and inexplicable act” need not mean that vulnerable groups should fear the treatment they would receive from Justice Zabel. “The evidence demonstrates that he is open-minded and impartial and that he does not exhibit any of the polarized, misogynistic, racist or homophobic views many of the complainants attribute to Donald Trump,” the council noted.

Zabel’s counsel said the judge – who has not been hearing cases since December –was eager to return to the bench. “Justice Zabel is very anxious to return to work,” said Giulia Gambacorta, one of his lawyers. “It’s been a long process, it’s been a very public reckoning for Justice Zabel and he’s really contrite – he’s been very contrite from the first day.”