The recordings were presented by the corporate regulator ASIC as it opened its trial against Westpac over alleged misconduct and market manipulation of the BBSW.
"Westpac understood the significance of the BBSW rate set process," counsel for ASIC Philip Crutchfield QC told the court.
The BBSW is a key interest rate benchmark used by a bank to set their own rate for business and personal lending and ASIC alleges this was manipulated so they could charge more for their loans to boost their own profits.
Crutchfield said audio recordings of Westpac's gun trader Colin Roden confirmed there was a strategy to "move the rate".
In one recorded conversation played to the court, Roden tells a colleague "I'm going to f... the rate".
"In this context, it means 'manipulate' and Mr Roden used it quite a number of times," Crutchfield said.
ASIC also tendered transcripts of Roden telling another trader: "I know it was completely wrong, but I thought f... it, I might as well f... it".
The court was also told that recordings and emails also contained references to "push the rate set higher'', "dish it out so it moves higher" and "trashing it", all of which allegedly showed Westpac's true intentions.
Westpac was one of three banks which faced trial on allegations of rate rigging between 2010 and 2012. ANZ and NAB have reached in-principal settlements with ASIC to pay penalties which are believed to be $50 million each.
Westpac responded by saying the phone calls between its traders were taken out of context because "it's the best ASIC can do" to try and prove allegations of rigging the bank bill swap rate.
The landmark case continues.
Business News Australia
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