The Sarbanes Oxley Act came in to force in 2002, and was introduced to force in the major changes to the regulation of financial practice and corporate governance.
It is the single most important piece of legislation which had the stated objectives: "to protect investors by improving the accuracy and reliability of corporate disclosures made pursuant to the securities laws".
It was intended deter and punish corporate and accounting fraud and corruption, ensuring justice for the wrongdoers, and to protect the interests of the workers and the shareholders.
Laws are there to aid in our tendency to act in our self-interest.
There are plenty of such laws which are related to business ethics.
Such as the international copyright laws, Sarbanes Oxley Act, and patent laws have aided in improving the organisational structures, and their cultures.
Without these laws there would have been no restrictions on people and organisations on piracy, copying brands, their names, their products, etc.
Without the Sarbanes Oxley disclosure act, it would have been quite easier for people to prepare fake documents with improper statistics and edited information.
It would have been quite difficult for organisations, and business to work in a trustworthy and ethical environment.
These kinds of laws have helped in removing the impurities or unwanted elements from the whole structure of the organisations, with respect to the suppliers, customers, entrepreneurs, retailers, etc.
All the laws have helped in developing the required guidelines for the businesses to act upon and flourish, and make the organisation perceive their responsibilities in the right manner.