"That is very painful for our clients."
Manning is acting for the Afghan villagers after New Zealand soldiers were involved in a 2010 operation in the Tirgiran Valley, which is now the subject of an inquiry.
A memorandum prepared by Manning and Harrison, seen by the Herald, stated that at the outset villagers had expected to receive all relevant information about themselves and the events of Operation Burnham.
"Regrettably, however, our clients have come to see themselves as consistently marginalised throughout the inquiry process," the memorandum said.
"Their personal concerns over their marginalisation have been persistent and steadily increasing.
"Our clients have a long-standing mistrust of the New Zealand authorities and Western governments more generally. That is completely understandable.
"Despite that, our clients were willing to believe that New Zealand might just be different in their case, firstly given the publication of Hit and Run [book] and the commitment of the authors, Messrs Hager and Stephenson, to tell their story and secondly through having obtained legal representation."
However, their clients believed a series of inquiry decisions had marginalised them from the process.
Their clients were adamant they should have access to video footage of the attack on their villages.
In a statement, an inquiry spokesman said they remained confident it would get to the truth of the matters under scrutiny "despite the withdrawal of the Afghan villagers as core participants".
"The withdrawal comes just two weeks after the Inquiry, in response to previous concerns of counsel for the villagers, had proposed (in Minute No 16) a process whereby it would travel to Afghanistan to hear evidence directly from the villagers.
"The Inquiry stands by the processes it has adopted. It has carefully struck a balance between safeguarding classified information and the identity of all witnesses while meeting the principles of natural justice and open justice.
"While the withdrawal of the Afghan villagers so late in the piece is disappointing, it does not significantly impact the Inquiry's work as the Inquiry has a wide range of information and sources available to it. This includes the authors of Hit & Run who obtained much of their information from the villagers, and the affidavits of three villagers filed in earlier court proceedings."
Inquiry into Operation Burnham
New Zealand forces entered Afghanistan amid the United States-led invasion that followed the September 11, 2001 terror attacks.
In August 2010, New Zealand forces took part in Operation Burnham in Tirgiran Valley in the Baghlan Province.
An explosive book, Hit & Run, that claimed six civilians were killed and 15 others wounded during the operation, was published in 2017.
The following year it sparked a Government inquiry to be led by Sir Terence Arnold, a former solicitor-general and Supreme Court judge, and former prime minister Sir Geoffrey Palmer.
The New Zealand Defence Force has rejected the book's claims, saying nine insurgents were killed.
Yesterday the Herald reported that the country's watchdog for spy agencies had been thwarted for months when trying to see secret emails about the controversial raid.
The Inspector-General of Intelligence and Security, Cheryl Gwyn, was given access to "several tens of thousands of emails" - then discovered another 115,000 were apparently overlooked.
