Carole Migden, the powerful head of the Democrat caucus in the California State Senate, has changed her story about the series of accidents she caused (the number has climbed from two to three in one day)  over a 20 mile stretch of busy freeway, sending a mother and young child to the emergency room by seriously rear-ending their Honda with her state-leased SUV. At first she claimed she was reaching for her cell phone, but when she encountered mockery over her vote for a bill outlawing speaking on a cell phone without a headset or hands-free set-up, it was time for Plan B.

State Sen. Carole Migden, whom the CHP now says may have been involved in as many as three traffic accidents last Friday, today revealed publicly for the first time that she has been battling leukemia for the past decade and that medication she takes may have caused her to become disoriented while driving.

"My only explanation is that it is medically related in some way," Migden, 56, said in an interview with The Chronicle.

The Democratic lawmaker who represents San Francisco and Marin County said she plans to underdo neurological tests to try to determine what may have happened.

"I owe an explanation to the public and myself, and in particular the person I hurt,'' she said, referring to the driver of a Honda sedan that was slightly injured in a rear-end collision. "I don't have a recollection of what happened. I can only conclude I had a medical event I can't explain. It's not an excuse; it may be an explanation."

"She kept saying, 'You can't talk to me like that, I'm a state senator,"' he said. "She was kind of wobbly. She didn't seem alert. She was not acting normally."