After the House rose today, a visibly angry Mallard denied the accusations.
Most of the usual Parliament business of the day was suspended this afternoon for the election of the new Speaker, Adrian Rurawhe, who was supported in the debating chamber with a waiata from his family members.
Following the music, Sharma rose and - using Parliamentary Privilege - accused now-former Speaker Mallard of ignoring concerns he raised about bullying within Labour.
Parliamentary Privilege gives MPs speaking in the debating chamber legal immunity from prosecution - including on things like defamation - to ensure members are not limited too much in having a robust debate.
The MP for Hamilton West was expelled from the Labour caucus yesterday for repeated breaches of caucus confidentiality and bringing the party into disrepute. He had spent the past fortnight making allegations of bullying and gaslighting by party whips, fellow MPs and staff from the Prime Minister's office.
Rising in the House this afternoon, he praised the words of Rurawhe.
"It was really refreshing to hear about fairness, about bringing value to the house, and changing some of the issues that are present in the House. It almost seems like you should be an independent rather than aligned to any side."
"Two weeks ago, I contacted the ... former Speaker and I went to talk to him about some of the issues I was having and whether I could get legal support in my case.
"The Speaker said 'If you raise anything about a Labour colleague, any challenges, it would be the end of your career'. And then the Speaker ended up going to the whips office, the Labour whips office, right after that to tell them that I had actually laid a complaint against the party and the whips," Sharma said in Parliament.
He was interrupted by Rurawhe, who said the matter was not relevant to the debate.
"I encourage the member, I will interrupt him again if he goes off-track. This is about the newly elected Speaker."
Sharma gave some final comments to say he hoped Rurawhe "would be a neutral person as a Speaker of the House and would show the fairness that you've talked about and would listen to members from all sides".
"And I just want to congratulate you on your new role as the Speaker-elect."
Several senior Labour ministers criticised Sharma's conduct, saying today was the day to honour and welcome Rurawhe as the new Speaker.
Mallard is off to Ireland as New Zealand's Ambassador, 38 years after he first started working in Parliament, and is expected to begin the post in Dublin in January next year.
