According to a police source, alcohol wasn't the reason for the incident even though Michael Phelps said that he was drank a beer about an hour and 15 minutes berfore he got the accident last week.

Last Thursday, Phelps' Cadillac Escalade crashed a Honda Accord driven by a Maryland woman. Phelps showed no signs of alcohol impairment, and he was not given a field sobriety test.

A police source confirmed that there was no alcohol or drugs involved. Investigators found that the Accord's driver, Amanda E. Virkus, was at fault for the crash. She will be cited for failure to obey a red light, and for causing an accident.

But the 24-year-old swimmer will also be cited too because of his invalid, out of state license. When police arrived on scene following the mishap, the Olympic swimmer, who holds the Olympic record with 14 gold medals for swimming, presented an invalid Michigan drivers license.

According to a police source, the Michigan license was no good because Phelps did not pay an earlier fine for not showing proof of insurance. A source said, "It looks like he didn't pay a reinstatement fee, and the license was suspended."

Phelps will have to attend in court to explain why he was driving without a valid license. In 2004, Phelps was sentenced to 18 months' probation due to driving while impaired.

Phelps wrote on his Facebook page that he is nursing a sore ankle stemming from the Thursday crash, but that he plans to train as scheduled on Monday.