Final answer:
The Illinois Human Rights Act protects classes similar to those of Title VII of the Civil Rights Act of 1964, including sexual orientation, which, while not broadly protected under Federal law, is protected for federal employees and in security clearance issues.
Step-by-step explanation:
Under the Illinois Human Rights Act, several classes are protected against discrimination, which are similar to those outlined in Title VII of the Civil Rights Act of 1964. These classes include race, color, religion, sex, national origin, ancestry, age, order of protection status, marital status, physical or mental disability, military status, sexual orientation (which includes gender-related identity), and unfavorable discharge from military service. It's important to note that while sexual orientation is not a protected class under Federal civil rights law as a general matter, it is protected for federal civilian employees and in federal security clearance issues. Additionally, the Supreme Court has implied that states may not prohibit protections prescribed by antidiscrimination law for gay people.