Societe Generale and controlling access

Societe Generale, a European bank, reported in January of 2008 a trading loss of nearly 7.2 billion dollars, one of the largest trading losses in banking history. How did they loose so much? Apparently an employee changed roles within the company moving from compliance to trading. While he was given the new permissions associated with his new role the permissions associated with his old role were never removed. Using his extra access rights and his knowledge of how compliance was managed the employee was able to make high risk trades in amounts far exceeding what he should be allowed. The result 7.2 billion in losses.