Refusal to comply with city ordinance.
An African-American seamstress from Montgomery, Alabama, in 1955 the 42-year-old Ms. Parks challenged the constitutional legitimacy of segregation laws when she refused to give up her seat on a city bus to a caucasian rider. A massive bus boycott followed that crippled the local transit system.
Arrested. Her actions are also widely recognized as the critical starting point of the civil rights movement.