Cato argued the prosecution had not made its case beyond reasonable doubt and the evidence of Crown witnesses was inconsistent and at times confused.
The lawyer claimed Petricevic had no knowledge of missed maturity payments to investors until just before the company went into receivership and was left "out of the loop".
According to the Crown, Bridgecorp began missing payments from February 7, 2007, when it failed to pay $206,000 due to investors.
Roest gave evidence earlier in the trial that he was aware of issues with payments in February 2007 and said he discussed these with Petricevic in morning meetings at the time.
However, Cato said the court could not place any significant weight on Roest's evidence and suggested no such discussions with Petricevic took place.
It was "human nature" for a co-accused to attempt to "mitigate their position" when standing trial, Cato said.
Cato also said Roest, as finance director, had a more hands-on role at Bridgecorp than Petricevic, whose job was to grow the business.
"Mr Petricevic was not hands-on ... the people that were hands-on were Mr Roest and Mr Jeffcoat [the former general manager of Bridgecorp]."
The lawyer labelled Roest a central figure within the company, who had "his finger well and truly on the financial pulse of Bridgecorp".
If anyone knew about the company's obligations to report issues to the trustee, it was Roest, Cato said.
Roest was in "serious dereliction of his duties" by not informing other directors and Bridgecorp's trustee about the payments, Cato said.
Using Roest's evidence to allege Petricevic knew about missed payments also put the Crown in a very "awkward position", he said.
Cato said the Crown wanted to use the evidence as a "leg-up" in the case against Petricevic but had been "most vitriolic in their treatment" of other parts of Roest's defence.
On Monday, Roest's counsel is due to begin giving closing submissions. That will be followed by final arguments in Steigrad's defence.
Justice Geoffrey Venning, who is hearing the trial alone, has indicated he will deliver his verdict on April 5.