Graeme Samuel has castigated business and regulators declaring that if another royal commission were called it would likely find the same "horrific" behaviour as in banks and aged care.

Mr Samuel chided a panel including NAB chairman Ken Henry, Woolworths chief executive Brad Banducci and corporate regulator James Shipton,  days before he hands over his report into the capability of the Australian Prudential Regulation Authority to federal Treasurer Josh Frydenberg.