The judge in the South Canterbury Finance trial has decided to continue to preside after an application was made by defence lawyers for him to be thrown out.
The failed finance company's former chief executive, Lachie McLeod, and former directors Edward Sullivan and Robert White, face 18 fraud charges at the High Court in Timaru.
The charges, brought by the Serious Fraud Office, include theft by a person in a special relationship, false statements by a promoter, obtaining by deception and false accounting.
On Monday, defence lawyer Bruce Squire, QC, argued that Justice Heath should stand down because he might be biased in favour of the SFO.
He said that SFO director Julie Read was heard at conference saying the office was fortunate to have that judge presiding over the case.
Mr Squire said based on that, Justice Heath's impartiality could be called into question by a reasonable lay observer.
But Crown lawyer Colin Carruthers, QC, said the comment was common courtesy and wouldn't be interpreted that way.
Justice Heath said the defence couldn't prove its case.