The lurid communications on which ASIC relies "don't support the alleged practice" of misconduct in the bank bill market around six years ago, Westpac's counsel has insisted on the final day of a six week civil trial in the Federal Court."ASIC's assertions that Westpac had the opportunity and the financial incentives to engage in the rate set trading practice are overstated," Matthew Darke told Justice Jonathan Beach at a hearing in Melbourne yesterday."The communications really have to be treated with caution," Darke said, cautioning the court on "the unreliability of inferring a practice from the communications … The communications are all ambiguous, they're all capable of different meanings."Refuting another ASIC theme, Darke said that the profits Westpac might have made - had it engaged in the market mischief - "are not particularly significant" while "any gains for individual traders in a form of high bonuses would be vanishingly small."The bank's treasurer, Curt Zuber, had, he said, sworn that "gains of the kind alleged by ASIC to have been obtainable [from minor shifts in BBSW] … would have been impossible for me to discern."As a result, Darke argued, the poorly remembered conversations extracted from audio records, "When viewed in their context, they are all capable of being interpreted as conveying legitimate meanings."Each treasury witness and Zuber, the treasurer for the bank, "have come to court and been cross-examined attesting to the innocence of their conduct," Darke told the court."All of them were honest and none of them made meaningful concessions in support of the ASIC case."Justice Beach voiced empathy for Darke's argument."To the extent that you are saying these are legitimate trading purposes you've called everyone down from Zuber that was available."In a riposte to legal argument by ASIC that Westpac failed to produce sufficient evidence, Darke told the court "deficiencies in ASICs' case aren't for me to make good. If instances of manipulative trading are lacking, it's not for me to prove there weren't any … we've answered everything put against us."