Mr Phillips has headed the EHRC since it was created in 2006
UK equalities chief Trevor Phillips will face a parliamentary inquiry over claims he tried to influence a committee writing a report on him.
MPs backed calls by its chairman Andrew Dismore to refer the matter to the Commons standards committee.
But another committee member said Mr Phillips had done "nothing improper" and had faced a "show trial".
The committee had investigated the Equality and Human Rights Commission after a spate of resignations.
They decided to call for the contempt inquiry after a meeting on 9 February when, they said, it emerged that Mr Phillips had contacted at least three members about consideration of its draft report and publication of written evidence.
Ms MacTaggart said she was one of the three and told MPs: "I don't believe that Mr Phillips has acted in contempt, he wanted to discuss whether the proposed report would be fair, because he believed, rightly as it turned out, that parts of the evidence that the committee received would be redacted in the final report."
She said she did not know how he knew that but said: "There was nothing improper or attempting to interfere with my ability to say what I wished."
Ms MacTaggart criticised aspects of the committee's inquiry - saying it had "no terms of reference".
"I was able to attend only one evidence session and I have to say it was more like a show trial about an individual than inquiry into the work of an organisation".
Ms MacTaggart said the standards and privileges committee, which will investigate whether Mr Phillips was in "contempt of Parliament" should also look at Mr Dismore's joint committee on human rights "to consider carefully if it operated in a way that was proper".
'Very new member'
Implying that MPs and peers "might be inhibited in their work by a telephone call from someone whose career might be put at stake by a report they are considering" was a "misuse" of Parliamentary privilege, she said.
Mr Dismore responded that Ms MacTaggart was "a very new member of the committee and had not participated in most of the inquiry.
"So her views may have been somewhat clouded by the fact she had not heard most of the evidence first hand, as we had."
MPs backed the inquiry without a vote.
But the Conservative backbencher Richard Shepherd also expressed concern about the way Mr Phillips had been accused of contempt adding: "I can think of nothing more damaging to the reputation of an individual than to have a paper produced in front of this house which says 'allegation of contempt'."
He questioned whether he would have known he was "at risk of offending against the privilege of the House" by phoning committee members.
It is unusual for someone who is not a politician to be investigated over a possible contempt of Parliament - the last to be called to the House to be formally rebuked was Sunday Express editor John Junor in 1957.
But in January MPs backed another contempt inquiry by the Commons standards and privileges committee into a law firm at the request of Lib Dem MP John Hemming.
Mr Dismore's committee had been investigating the work of the equalities watchdog, after several commissioners and the chief executive resigned.
Mr Phillips appeared before them in December and defended himself against accusations he surrounded himself with a "clique" and that other commissioners felt they could not speak.
He said he did not "recognise" that picture and most members of the board had no trouble disagreeing with him, or each other.
But in February the committee published a statement saying it had emerged that Mr Phillips had "recently spoken to at least three members" about its draft report.
"In our view these discussions could constitute a contempt of both Houses in that they may be an attempt to influence the views of certain members of the committee shortly before it considered a draft report directly relevant to Mr Phillips in his role as chair of the EHRC," it said.
Earlier this month the Equality and Human Rights Commission said: "Neither Mr Phillips nor the commission is aware of any reason why any of his actions might amount to a contempt of the Houses of Parliament.
"Should the parliamentary authorities decide to take this matter further both Mr Phillips and the commission would be happy to cooperate fully."