Speaking after a panel on "Strengthening the social contract of banking" at the Banking & Finance Ethics day, Stephen Mayne had his Shareholders Association hat on - but also made it clear he was giving his personal view - when he noted that Australia is the only country in the world where four of the top five companies by market capitalisation are banks.Mayne warned this was drawing fire for the banks and much more needed to be done."The government could come along and put a cap on salaries. They could start fixing prices on mortgages and fees. The government regulators could dramatically change the capital requirements," he said."While the banks are making A$50 billion pre-tax that will be seen as too much and unless they walk that down to $40 billion, or even $30 billion, the government will do it for them."The audience of banking and "triple bottom line" advisers had earlier heard from Professor Justin O'Brien, Australian Centre for Financial Studies at Monash University,  who noted that worldwide banks have paid up to $320 billion in penalties to the end of Q1 this year. In some cases, whistleblowers were paid between ten and 30 per cent of the money received by Government after successful actions. "The fine was ultimately negotiated by government regulators and no-one was paid the reward unless it was shown concerns were first raised within the organisation.