This is becoming all to common. It is the job of the police to question people if they think a crime has been committed or if they think that person may have been a witness to a crime.
Not to many years ago it was simply called an investigation and you questioned anyone involved, or believed to be involved regardless of ethnicity. Something has gone terribly wrong here.
Oh no! You can't question possile criminals about a crime. That would be criminal class profiling. Also this would be a violation of their first amendment and their right to jury nullification!
There will be no more criminal investigations as per our constitution, the ACLU and the left wingers lust for those who commit crimes! In fact there will be no more crimes! If there are no more crimes, everyone will be happy! :)