Late Thursday, MGM Mirage (NYSE: MGM) CEO and Chairman J. Terrence Lanni stepped down from his position after reports surfaced that he had falsely claimed to have earned an MBA degree from the University of Southern California.

The news came following reports that several public companies had executives whose biographies listed college degrees they didn't earn. The University of Southern California had no record of Lanni's degree.

MGM Mirage became aware of the situation after someone from USC contacted the company to warn it about inquiries regarding the degree from the Wall Street Journal and fraud investigator Barry Minkow. Lannni says that his sudden resignation has nothing to do with the credentials issue, and that this move was based on his desire to live with his wife again, who has been living in California.

It's hard to believe Lanni. Like other gaming companies, MGM Mirage is struggling because of the economy. This is no time for the resignation of the CEO with no warning or notice. Adding to the unbelievability factor is Lanni's explanation. Like other executives caught fabricating their credentials, he came up with a silly (and untrue) story to cover the deception: He says that he took MBA classes and never finished the degree, but was awarded an honorary MBA from the school in the 1970s.