McCullum is paying for the case and is not seeking monetary damages.
"I simply want his [Parker's] acknowledgment that the claims he makes are completely false.''
Coach Mike Hesson has also instructed lawyers to threaten legal action. When contacted he said: "The matter is in the hands of my lawyers. I have no further comment.''
Gallaway could not be reached for comment, nor could Parker's lawyer and fellow director in The Sport Management and Training Group, John Wiltshire. Parker is currently in the Middle East on business.
Any legal action issued by McCullum and Hesson is expected to target the original recipients of the unfounded allegations and anyone, including media, who published, forwarded or broadcast it.
The Parker movement's main aim has always been to gain more influence on the New Zealand Cricket board for former players. Until past national representatives Ian Smith and Mark Greatbatch officially came forward, Parker
had been alone in being prepared to attach his name to the group in the interests of focusing on principles rather than personalities. That came undone with the release of "The Taylor Affair'' and an email trail earlier this month, time-lining alleged recent incidents within the team.
The Herald contacted as many as possible of the more than 20 names on Parker's email list. Almost to a person they either did not return calls, did not want to be named, claimed to be part of the email chain but didn't have input into the report, or had unsuccessfully requested to be removed from future correspondence. The level of commitment to the cause suddenly became scant.
The issue raises questions about the credibility of the Parker movement in pitching forth potential board members, especially if hearsay, speculation and rumour were reported as fact in "The Taylor Affair".
There can be no doubting Parker's passion for the game and his intentions to improve the current circumstances by adding to a board and administration which has struggled to deal with the Taylor captaincy saga.
Speaking earlier this month, Parker said he wanted the focus to be on the governance of the game rather than it becoming "a Ross Taylor vs Brendon McCullum issue.''
Parker said: "It's wider than that. That was just meant to be an example of poor governance... We're focusing on the revamped constitution and the appointment of good board members.''
Greatbatch, who worked in a coaching role with New Zealand until John Wright's appointment as head coach in December 2010, felt compelled to support Parker a fortnight ago.
"I want what is best for New Zealand cricket and I'm not sure the people in governance are currently making the best decisions. Sure, everyone makes mistakes but this time we've got to learn from them.
I'm happy being part of a movement which wants to help make informed decisions so we don't have the multiple incidents which have recently detracted from our game."