"Mr McKay's failures to this client were many and obvious. The consequences to her of his failures were devastating. He enabled her home to be purchased by another client at a gross undervalue," Judge Clarkson said in the decision on penalty.
According to the tribunal, McKay's defence involved an attack on the honesty and integrity of his client.
"We considered that Mr McKay attempted sophistry and at times plain untruthfulness to escape facing up to the responsibility of his acting in this position of irremediable conflict," the tribunal said.
The tribunal said McKay's submissions on what penalty was appropriate "lacked any element of remorse or insight into his failures".
"They were self-pitying and relentlessly self-absorbed," the decision said.
Although McKay said he wanted a second chance, the tribunal considered his striking-off was necessary.
"We can have no confidence that Mr McKay would not, if able to continue to practise, repeat his actions, given his sense of self-righteousness and justification for his actions," Judge Clarkson said.
McKay, as well as being struck-off, was ordered to contribute $70,000 to costs and reimburse the Law Society $14,812 for hearing costs.
"This particular lawyer strayed so far from the path of professionalism that he can justifiably be said to have ceased to function meaningfully as a lawyer at all. It is rightly expected that lawyers act for their clients without conflict of interest or any form of bias," New Zealand Law Society President Chris Moore said.
"The vast majority of New Zealand lawyers act independently and in the best interests of their clients by providing exceptional service which is totally focused on their clients' interests."
