Your attorney, whether retained counsel or public defender, should do that without having to be told. But remember that what you think might be a constitutional violation might not be so under the law and your lawyer is not going to make arguments that are without legal basis. As to when and how such claims are advanced, that is a matter of state and local practice, and you will need an Arkansas attorney to address that.
If you are looking for your public defender to "advocate" violations of your civil rights, they will only handle the criminal aspect of the case. (Motions to suppress evidence based upon an illegal search/seizure etc.) If you are looking for someone to advocate civil rights violations such as injuries suffered from excessive force, etc. then you will need a civil attorney to handle those types of actions. Your question is a little vague in what you are really wanting the attorney to do.
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