Michael Bain did not know his dead brother, Robin, well enough to say publicly he was not a killer, David Bain campaigner Joe Karam says.
• Robin Bain no killer, says brother
Michael Bain broke his silence for the first time this week describing his brother as a "loyal, peaceful and thoughtful" man and "no killer".
Robin Bain, his wife Margaret, and the couple's three children Arawa, Laniet and Stephen, died in the family home in Dunedin in 1995.
David Bain was found guilty of the murdering all five and spent 13 years in prison before he was found not guilty in a retrial in Christchurch in June.
The retrial was told by counsel for David Bain that his father was depressed and had killed his family in their Dunedin home before killing himself.
Michael Bain, writing in The Listener magazine, said the family found the retrial difficult to accept because none of those against whom "hearsay" allegations were levelled were alive to rebut them.
However, Mr Karam told NZPA Michael Bain had seen his brother less than six times in more than 20 years before the killings.
"It is nice that he loves his brother but I think he is in denial, really.
"The evidence was very clear he (Robin) was in a seriously declining mental condition."
Mr Karam led the battle to take the case to the Privy Council in England which led to the retrial and not guilty verdicts for David Bain.
Another group, fighting to clear the name of Robin Bain, said Mr Karam had never met him and could not pretend to know better than Michael Bain about his brother's character.
