Most top notch criminal defense lawyers will charge retainers of $5,000 to $100,000 depending on the type of assault charged and the level of injury. Most assault cases are prosecuted in state court. The retainer a lawyer charges largely depends on the seriousness of the case.
There are five degrees of assault. From first to fifth degrees, they are governed by Minnesota Statutes 609.221, 609.222, 609.223, 609.2231, and 609.224, respectively.
First degree assault has two possible offenses. The first is an assault inflicting great bodily harm, which may be punished by a maximum of 20 years and/or a fine of up to $30,000. The second is an assault with deadly force against a police officer or correctional employee. This offense may be sentenced by up to 20 years in prison and/or up to a $30,000 fine. See https://www.revisor.mn.gov/statutes/?id=609.221.
Second degree assault occurs when a person assaults another with a dangerous weapon and carries a sentence of up to 7 years in prison and/or up to a $14,000 fine. If substantial bodily harm results, the sentence is up to 10 years in prison and/or up to a $20,000 fine. See https://www.revisor.mn.gov/statutes/?id=609.222.
There are three possibilities for third degree assault, all of which carry a prison sentence of up to 5 years and/or up to a $10,000 fine. First, if substantial bodily harm occurs. Second, if the assault is of a minor (child abuse) and the offender has a history of abuse against the minor. Third, if the assault is of a person under age four and bodily harm results. See https://www.revisor.mn.gov/statutes/?id=609.223.
Assault in the fourth degree has many possibilities. This crime, for the most part, covers assaults against public officials, such as postal service employees, reserve officers, school officials, firefighters, police officers, and DNR employees. The sentences could be up to 3 years in prison and/or up to a $6,000 fine. The offense level could be a gross misdemeanor or a felony. See https://www.revisor.mn.gov/statutes/?id=609.2231.
Fifth degree assault can be a misdemeanor, gross misdemeanor, or a felony. The misdemeanor level is when a person intentionally causes another to fear immediate bodily harm or death or when a person intentionally causes or tries to cause bodily harm to another. The gross misdemeanor level is a misdemeanor assault that occurs against the same victim within ten years as certain domestic violence offenses. The felony level is a misdemeanor assault that occurs against the same victim within ten years of two or more certain domestic violence offenses. Fifth degree assault also covers assaults using a firearm. See https://www.revisor.mn.gov/statutes/?id=609.224.
Federal assault is generally governed by 18 U.S.C. § 113. The sentence depends on the facts. Assault with intent to commit murder, for example, carries a sentence of up to 20 years. Assault by wounding another carries a sentence of a fine and/or up to 6 months in prison. See https://www.law.cornell.edu/uscode/text/18/113.