The Australian corporate regulator is pushing ahead with a landmark case against some of Commonwealth Bank's existing and former board members over the organisation's anti-money laundering (AML) failures. The civil case is shaping up to be one of the first under the Australian Securities and Investments Commission's "litigation first" enforcement strategy, under the new deputy chairman, Daniel Crennan QC.The case is understood to be getting priority among more than 40 major cases that ASIC is exploring following the publication of the report of the royal commission into banking misconduct four weeks ago. ASIC is looking at whether CBA's most senior staff met their obligations of "care and diligence" in relation to systemic breakdowns in the bank's AML controls between 2012 and 2017.A spokesman for Commonwealth Bank said on Monday: "CBA continues to engage with ASIC regarding a number of matters and responds to requests made by the regulator. We won't be commenting on any individual matter."Former ASIC chairman Greg Medcraft highlighted the investigation prior to leaving the regulator in 2017 and the case has been built steadily behind the scenes since then. It is expected to become a fundamental test of the obligations on directors under the Corporations Act 2001.The investigation into CBA is looking at possible breaches of Section 180 of the Corporations Act 2001. If ASIC pursues this line in court, it will be a critical test case for the "care and diligence" obligations on directors.The regulator is looking for evidence to mount a civil case against at least five CBA directors. The investigation includes whether the bank allocated sufficient resources to fix the problems between 2015 and 2017.Section 180 of the Corporations Act requires directors and executive officers to act with care and due diligence, and to discharge their duties with a degree of care that a reasonable person would exercise as a director or officer of the company.Directors can make business judgements but are under a duty to inform themselves about the subject matter of that judgement to the extent that they reasonably believe to be appropriate. They must also act in good faith for a proper purpose and "rationally believe that the judgement is in the best interests of the corporation."The investigation into CBA's directors represents a new era in supervision and enforcement in Australia, with financial regulators working much more closely together on major cases.The historic Austrac civil claim against CBA, which ran to more than 600 pages, will form the backbone of the ASIC investigation. The bank settled the AML regulator's claim that it breached the Anti-Money Laundering and Counter-Terrorism Financing Act 2006 (AML/CTF Act) on 53,750 separate occasions. The case revealed that the bank had identified systemic problems with its AML/CTF controls as early as May 2015. The bank settled the litigation in June 2018 for A$700 million.A revised statement of claim in December 2017 showed the bank was still having problems with its basic AML/CTF controls. In one case the bank actioned a payment to a listed terrorist financier in Lebanon,