Final answer:
The unauthorized practice of law in Illinois is not directly addressed in the cases provided. Such matters are generally dealt with by the Illinois Supreme Court rulings or state statutes specific to the regulation of legal practice.
Step-by-step explanation:
The question regarding the unauthorized practice of law in Illinois does not directly relate to any of the provided cases, such as McDonald v. City of Chicago (2010), Presser v. Illinois (1886), Illinois v. Gates (1983), or Grutter v. Bollinger (2003). These cases dealt with issues of the Second Amendment, the legality of military drills, the establishment of probable cause under the Fourth Amendment, and affirmative action in university admissions, respectively. To accurately address the question about the unauthorized practice of law in Illinois, one would typically refer to the Illinois Supreme Court rulings or state statutes that directly address the regulation of legal practice.