Discrimination based upon the behavior of the individual is okay in some instances, otherwise we couldn't incarcerate bank robbers.
Hope you didn't mind the edit/clarification (if it accurately describes your stance).
The word discrimination versus the word prejudice seems almost an exercise in rationalization. Behavior includes more than criminal behavior. And even defined "criminal behavior" can be immorally prejudiced.
"The word prejudice refers to prejudgment: making a decision before becoming aware of the relevant facts of a case or event. The word has commonly been used in certain restricted contexts, particularly in the expression 'racial prejudice'. Initially this referred to making a judgment about a person based on their race, before receiving information relevant to the particular issue on which a judgment was being made; it came, however, to be widely used to refer to any hostile attitude towards people based on their race. Subsequently the word has come to be widely so interpreted in this way in contexts other than those relating to race. The meaning now is frequently 'any unreasonable attitude that is unusually resistant to rational influence'.[1] Race, gender, ethnic, sexual identity, age, and religion have a history of in citing prejudicial behavior."
http://en.wikipedia.org/wiki/Prejudice" Discrimination on grounds such as race or religion, is generally illegal in most Western democracies, while discriminating between people on the grounds of merit is usually lawful. The latter is more commonly referred to as "differentiating." When unlawful discrimination takes place, it is often described as discrimination against a person or group of people."
http://en.wikipedia.org/wiki/Discrimination