The Catholic Church teaches that the homosexual tendency is not a sin:
Although the particular inclination of the homosexual person is not a sin, it is a more or less strong tendency ordered toward an intrinsic moral evil; and thus the inclination itself must be seen as an objective disorder. - e.g. in Letter to the Bishops of the Catholic Church on the Pastoral Care of Homosexual Persons, 3, 1 October 1986 | CDF.
What is the scriptural basis, if any, for the Catholic teaching that the homosexual tendency is of itself not a sin?
This is a commonsensical principle of human responsibility that is presupposed by scripture (and every legal system in the world)I guess you've not heard of involuntary manslaughter, which people do go to jail for. A drunk driver hits another drive and the crash kills the sober driver. The drunk driver then goes to jail because of that person's death, not the DWI. This supposes that the breaking of the law leaves you responsible for subsequent accidental breakings of the law. – Jan 28 '15 at 20:14