Jurors in the tax conspiracy re-trial of millionaire contractors Peter Bartlett and Ron Sayers have been warned they should disregard a trial last year.
Justice Eric Heenan also warned jurors this morning they should not carry out independent research or take information from other people about the case.
The Supreme Court retrial of Mr Bartlett and Mr Sayers charges of conspiring to cause a loss to Commonwealth is expected to last up to eight weeks.
Justice Heenan gave a series of warnings to the jury and pointed to a much publicised case last week in which a jury was discharged and a trial aborted.
That unrelated trial was aborted because of information provided to the juror after an internet search was carried out by another person.
Justice Heenan today told the jury panel of 12 men and four women that a jury last year did not reach a verdict on charges against Mr Bartlett and Mr Sayers.
Tax consultant Gregory John Dunn was convicted of conspiracy in last years trial, but accountant Deborah Grace was acquitted.
Mr Bartlett and Mr Sayers have pleaded not guilty to conspiring with Dunn and accountant Trevor Neil Thomson to defraud the Commonwealth of $3.3 million for the 1998-99 financial year.
The plot was allegedly carried out from 1992 and 1994.
The trial could last up to eights weeks.
Ausdrill today formally announced the extension of Mr Sayers' contract as managing director.
The mining services provider said Mr Sayers' contract, due to expire at the end of June, had been extended indefinitely.
The company founder had previously flagged his intention to stay in the job.
The new agreement can be terminated by either side with 12 months' notice.
While Mr Sayers attends court, the company said he would continue to monitor and have input into the management of its business.
"Appropriate arrangements have been made to ensure he remains adequately informed as the activities and financial performance of the group, and generally as to the steps taken by management," a statement said.
The group's businesses would continue to be managed its two chief operating officers in Australia and Africa.
Ausdrill's securities went into a trading halt on Friday ahead of expected asset impairments. The shares last traded at $1.065.