The current pope (Benedict XIV formerly known as Cardinal Ratzinger) when he still was a cardinal pretty much wrote the "book" on what the Catholic church considers religious "doctrine"/"policy" when it comes to homosexuality.

The document is called "Letter to the Bishops of the Catholic Church on the Pastoral Care of Homosexual Persons" (written 1985 released 1986).
http://www.vatican.va/roman_curia/congregations/cfaith/documents/rc_con_cfaith_doc_19861001_homosexual-persons_en.html

Now this letter references (as a source of logic) the 1975 Declaration on Certain Questions Concerning Sexual Ethics which deals with many things that the Church considers sins relating to sex
http://www.vatican.va/roman_curia/congregations/cfaith/documents/rc_con_cfaith_doc_19751229_persona-humana_en.html

Now in the document it recognizes that Homosexuality is probably innate, and it recognizes a difference between being homosexual (aka having homosexual desires) and actively "sinning" (having homosexual relations.) If being a homosexual is innate you can't be excommunicated. Furthermore having homosexual desires itself is not sinful since it is innate, homosexual desires are "disordered" since it "tempts" you to sin, the actual acting on these desires is sinful. Being "disordered" is not the same as sinful, being "disordered" means more likely to sin.

The catholic church also (as doctrine, reality is sometimes a different matter) encourages love and respect for all homosexual people. Furthermore it is very much against persecution and violence of homosexual people. Finally in theory (but sometimes not in reality) the Catholic Church is against the criminalization of homosexuality.

Also if you have had homosexual feelings in the last 3 years, you are "supposed" to enter seminary and thus won't be able to become a priest, "in theory"

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On another note, while this is a taboo subject, Benedict XIV (Ratzinger) is very much a closeted gay man. Now I ain't saying he is having sex, I very much believe he is a chaste man, but that doesn't change the fact he is probably a very gay man who is in the closet.