Establishing a royal commission into the banking sector is emerging once more as a policy priority for the Labor Party.The idea of a royal commission has been "under active discussion" at senior levels in Labor for some time, the Financial Review reports on its website.Labor leader Bill Shorten mounted the case on Thursday for a royal commission, saying the government was wrong to have ruled it out."I think Australians are sick of politicians who talk tough and do nothing. I think it's frankly quite contradictory. Mr Turnbull is there giving some sort of lecture to the banks, then he wants to propose corporate tax cuts," the AFR reports Shorten as saying."It's time for Mr Turnbull to stop ruling out quickly the option of the Royal Commission and instead start listening to what every day Australians are saying and they don't like the bad behaviour of banks."If there was a building worker, a tradie, the Government is over them like a rash examining their behaviour. But the top end of town, the banks, the government is so quick out of the blocks to rule out a royal commission, it's breathtaking."