What credibility does a teaching authority have which everyone knows to be wrong?

Church teaching on contraceptives

The Catholic Church still officially teaches that the use of contraceptives is always wrong [background information here]. Catholics in Western countries have learnt to ignore this official Catholic teaching (see right column). But, as the above video shows, the Church still inflicts great hardships on the uneducated faithful in poor countries. Families, and especially women, suffer.

Moreover, even when condoms can prevent women from being infected with AIDS, Church authorities forbid it. The Catholic Bishops Conference of South Africa is still opposed to the responsible use of contraceptives in such cases. Only Bishop Kevin Dowling is the exception. "Because of my experience", he has stated, "I began to question as a Catholic church leader the perceived notions. I don't undermine the veracity of abstinence before marriage and loyalty among couples. But what about the vulnerable women who don't have that option? What about realizing that the official Church in circumstances of human living does not respond to that reality? . . . The use of condoms has been viewed as a sexual morality issue in the Catholic Church. But to me it is more of a justice and ethical issue -- the right to life, the protection and dignity of life, a pro-life stand from conception to death."

The video below shows the circumstances in which Bishop Dowling exercises his pastoral leadership.

Tragic incompetence

1963. Since the issue of contraception was raised at the Second Vatican Council, Pope John XXII established an international commission of experts to study the question. Pope Paul VI extended the commission to 72 members from five continents.
1966. The commission concluded [with a majority of 68 to 4!] that artificial birth control was not intrinsically evil and that Catholic couples should be allowed to decide for themselves about the methods to be employed.
1968. Rejecting the commission's advice, Pope Paul VI issued the encyclical 'Humanae Vitae' [Latin for Human Life] on 'the Regulation of Birth'. The encyclical restated traditional principles and, among other things, declared that the use of contraceptives was wrong 'in all circumstances' and could never be justified 'because it goes counter to natural law'.
See this video that recounts the whole story.

Today. In all countries with a high level of education, Catholics ignore the Church's prohibition and use contraceptives. In the USA, for example, 98% (!) of all Catholic women of reproductive age who have ever had sex have used a method of contraception other than natural family planning. Among women who are currently at risk of unintended pregnancy, 87% of Catholics use contraception: 68% of them employing sterilization, the IUD, the pill; 15% relying on condoms; 4% using other methods, such as withdrawal.
Guttmacher Report, April 2011