One of the so-called "Barbie Bandits" said stealing money from a bank was "a bad idea."

Ashley Miller testified Thursday in Marietta, Ga., in the trial of a man accused of organizing the bank heist. She called it the "worst decision I ever made."

Miller also testified that she and the defendant — Michael Darrell Chastang — were romantically involved.

Chastang was behind the February 2007 heist and put Miller and Heather Johnston in touch with the bank teller, authorities said.

Miller and Johnston made headlines after they were videotaped wearing sunglasses and laughing as they appeared to steal nearly $11,000 from a Bank of America in Acworth. But authorities said what at first looked like a bank robbery turned out to be a theft involving a complicit teller. They were arrested days later.

The four had split the money, authorities said.

Johnston, Miller and the bank teller, Benny Herman Allen III, have pleaded guilty to theft charges in the case and testified against Chastang.