I am in (secular) law school and am exploring my professional options. One of those options is to become a criminal defence attorney.
In my country of residence, attorneys qualified in a specific area of law are forbidden from rejecting clients on the basis that they are notorious or highly suspected of being guilty. If I am approached by a potential client who is able to pay my standard rate, and I am physically available to defend the person and am knowledgable in the relevant area of law, I am legally required to defend the individual.
Thus, it is possible that I would be legally required to defend someone who has violated one of the Noachide laws, etc. It is possible that in doing so, someone who I suspect is guilty would be acquitted on the basis of issues with the prosecution, in accordance with the laws of my country of residence. Although it is unlawful for me to lie in court, if a client who I suspect is guilty claims he is innocent, I would be required to try to make that case to the best of my ability.
What are my obligations in regards to Halacha, if I were to become a criminal defence attorney? I am aware that as a Jew I am required to distance myself from untruth, etc. Am I permitted to defend such people? What if, for example, such a person has clearly violated a Noachide law or harmed a Jew, but could be acquitted as a result of the prosecution having illegally obtained all of the evidence?