Additionally, discrimination on the basis of sexual orientation and gender identity is banned in employment, housing, credit and public accommodations, and conversion therapy on minors has been outlawed since 2016.

[5] 2019 polling from the Public Religion Research Institute showed that 74% of Illinois residents supported anti-discrimination legislation protecting LGBTQ people.

In 1913, in People v. Smith, the court held that cunnilingus was not a "crime against nature", stating that "without a male sexual organ, there could be no sodomy".

[6] Notably, sodomy was not legalized, but actually de facto decriminalized because the laws against the "infamous crime against nature either with man or beast" were not included in the Criminal Code of 1961.

[7] However, the code also made it a crime to commit a "lewd fondling or caress of the body of another person of the same sex" in a public place.

[8] In 1970, Illinois voters approved a constitutional amendment which grants people the right "to be secure in their persons, houses, papers and other possessions against unreasonable searches and seizures, invasions of privacy or interceptions of communications".

[14] In July 2021, the governor of Illinois signed a bill into law to legally provide individuals a gender-neutral marriage certificate available.

On January 31, 2011, Governor Pat Quinn signed legislation that recognizes same-sex civil unions, effective from June 1, 2011.

[19] In May 2012, Lambda Legal and the American Civil Liberties Union filed lawsuits in state court challenging the refusal of the Cook County clerk's office to issue marriage licenses to same-sex couples.

[23][24] The Illinois Human Rights Act states: "'Sexual orientation' means actual or perceived heterosexuality, homosexuality, bisexuality, or gender-related identity, whether or not traditionally associated with the person's designated sex at birth.

Illinois law prohibits bullying based on race, color, religion, sex, national origin, ancestry, age, marital status, physical or mental disability, military status, sexual orientation, gender identity or expression, unfavorable discharge from military service, association with a person or group with one or more of the aforementioned actual or perceived characteristics, or any other distinguishing characteristic.

[36] Effective from January 1, 2023 school students throughout Illinois with trauma for an "health and safety reasoning justification" on the basis of sexual orientation and gender identity - are to be legally protected explicitly within legislation.

When parties enter into a surrogacy agreement that complies with the state statute, no court action is required to obtain a birth certificate with the names of the intended parents.

[48] On April 16 and on May 20, 2015, the House and the Senate unanimously passed HB 3930 to add "gender identity" to the Illinois hate crime statute.

Even though reassignment surgery is not a formal requirement for a legal gender change anymore, if the applicant, aged at least 21, wishes to undergo the procedure, Illinois Medicaid will cover the costs.

[62][63] On May 31, 2017, the Illinois General Assembly passed legislation (by a vote of 63–43 in the House and 32–22 in the Senate) to abolish the sex reassignment surgery requirement.

[55][56] In June 2019, it was reported that a cisgender woman was denied a change of sex designation on her birth certificate, due to red tape as being incorrectly listed as a male decades ago.

[71][72] In February 2021, representatives Jennifer Gong-Gershowitz, Daniel Didech, Anna Moeller, Margaret Croke, Maura Hirschauer and Dagmara Avelar introduced legislation to the Illinois House to remove language from the vital records law requiring the State Registrar of Vital Records to issue a new birth certificate upon receipt of a declaration stating that the applicant has undergone treatment for the purpose of gender transition or that the individual has an intersex condition, instead providing that a new birth certificate must be issued by the State Registrar upon receipt of a statement signed by the applicant attesting to making the request for the purpose of affirming their gender identity or intersex condition and that the sex designation on the person's certificate should therefore be changed.

[84] In May 2023, a very similar bathroom bill formally passed both houses of the Illinois General Assembly - with numerous amendments to "not force businesses and/or restaurants of any size to change signage, doors, urinals or disrupt interstate commerce", instead just "permit and allow" gender-neutral usage of bathrooms within Illinois for transgender and non-binary individuals throughout the state.

[86][87] In July 2020, the Lurie Children's Hospital apologised for past usage of surgery on intersex infants to make their genitalia appear more typically male or female without proper consent.

[96] Sex education lessons in Illinois are not compulsory, but schools that do teach it must provide students with age-appropriate, evidence-based, and medically accurate information concerning contraceptives and sexually transmitted diseases (including HIV) through Year 6 to 12 (age 11–18).

Among others, the order established a task force to direct the state Board of Education to promote transgender students' rights in schools and develop procedures for concerns such as names, pronouns, and dress codes.

"[115] In August 2021, the governor of Illinois signed a bill into law - that implemented immediate restoration of US military service benefits for discharged LGBT veterans (prior to the September 2011 repeal of the US DADT policy).

[116][117] A February 2013 Crain's/Ipsos poll found that 50% of Illinois residents favored the same-sex marriage bill under consideration by the General Assembly, while 29% opposed it.

[118] A majority of Illinois residents supported civil unions, health benefits for partners, and protections from hate crimes and discrimination.

[120] According to a poll conducted between February 28 and March 10, 2015 by Southern Illinois University Carbondale's Paul Simon Public Policy Institute of Illinois 54.9% of registered voters supported same-sex marriage, 20% favored civil unions, 6.7% of voters were unsure, and only 18.4% opposed both marriage and civil unions for same-sex couples, meaning 74.9% supported legal recognition of some kind.

[121] A 2017 Public Religion Research Institute (PRRI) opinion poll found that 65% of Illinois residents supported same-sex marriage, while 25% opposed it and 10% were unsure.

[122] The same poll found that 71% of Illinois residents supported an anti-discrimination law covering sexual orientation and gender identity, while 21% were opposed.

[124] A 2022 Public Religion Research Institute poll found that 77% of Illinois residents supported same-sex marriage, while 20% opposed it and 2% were unsure.

The same poll found that 85% of Illinois residents supported an anti-discrimination law covering sexual orientation and gender identity, while 12% were opposed and 3% were unsure.