He alleges that Currie knew a key witness, who has permanent name suppression and is only known as L, was getting a lighter sentence in exchange for testifying in his case.
Before or during the trial, Clayton and co-accused Linda Westbury, Peter Machirus, Nadia Pelenato, and Gary Morell who are also suing Currie and the Crown, learned that L had been charged with subsequent, unrelated offences at Wellington District Court.
They wanted to know if L was getting any discount on their sentence for helping police, including giving evidence during their trial.
They allege that Currie didn't pass on all information about L's sentencing indication, which they claim helped the jury come to guilty verdicts.
In 2009, the Court of Appeal quashed Clayton's convictions and ordered a retrial.
But the retrial never happened as the Crown dropped the case.
Clayton and Westbury today claimed that the events still hinder their day-to-day life.
They claimed that Currie's "deceitful and intentional" actions "strikes at very heart" of the New Zealand justice and its integrity.
The pair are suing for compensation - Clayton $1m for losses and reputational damage, and Westbury $575,000 for losses, reputational damage, and mental and emotional suffering - alleging misfeasance in public office and breach of their rights under the New Zealand Bill of Rights Act.
Clayton claimed that Currie acted with malice towards the defendants with a "win at all costs mindset".
Machirus, Pelenato and Morell are suing over alleged misfeasance in public office, breach of the New Zealand Bill of Rights Act, and deceit. Morell also alleges malicious prosecution.
Appearing for the defendants – Currie, the Crown Solicitor at Christchurch, and the Attorney-General, John Pike QC said it was a "highly unusual" case.
Currie admits making an innocent "blunder", Pike said, but there was never any attempt to deceive or deny rights to a fair trial.
And there was no intervention in the Wellington sentencing process, Pike said. Christchurch's Crown lawyers were in the dark when details of L's sentencing indication emerged, he told the court.
Currie's "blunder" was accepted by the Court of Appeal, Pike said, and ultimately cost the Crown its case.
But it went no further than that, he argued, and Currie had no more interest in the Operation Rhino case than any others that came before the court.
"Nothing marked these plaintiffs out for special attention," Pike said.
The hearing, before Justice Peter Churchman, continues. It is set down for nine days.
