American commercial, military, governmental, and even ecclesiastical establishments have for months enforced mandates to penalize conscientious objectors to COVID-19 mRNA vaccines. All these vaccines have some connection, more or less remote, to abortion. Yet, though the United States Conference of Catholic Bishops (USCCB) recognizes this connection, several dioceses have conflated the teaching of the Church with scientific or prudential judgment about the common good. This has led many bishops to dismiss legitimate concerns felt by individuals with sensitive consciences. In so doing, these bishops ignore the Church’s teachings on the grave duty to obey one’s conscience.

The Church has from its beginning considered abortion to be murder. No less clear is its teaching on reverence due to the human body—never to be an item of economic trafficking. No body part should be taken for another’s benefit unless the donor gives consent. So a Catholic may have a reasonable conscientious conviction that any profit from such activities is cooperation in sin.

Obligations of Conscience

Even though it condemns the use of aborted children’s remains for medical and commercial enterprises, the USCCB in December 2020 wrote, “being vaccinated safely against COVID-19 should be considered an act of love of our neighbor and part of our moral responsibility for the common good,” because of “serious obligations such as the prevention of deadly infection and the spread of contagion.” They urge Catholics to communicate their objections to vaccines’ use of fetal cell lines as they accept the vaccines.

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However, it is inconsistent to object to an activity but withhold protections for or even punish those who avoid participating in it. Large dioceses such as El Paso threaten employees with dismissal if they refuse this vaccination on religious grounds, and make no effort to find ethical alternatives. Smaller dioceses, such as Burlington, Vermont dismiss priests for refusing the shot.

Regardless of new data and scientific findings, we must always be careful to avoid moral error—and conscience is our primary guide in avoided moral error.


Church leaders justify their dismissal of individuals’ moral objections to vaccines by laying the blame on those who actually developed the vaccine. For example, the bishop of Lubbock sought to erase conscientious concerns about the vaccine by explaining that “[t]he real order of moral concern is on the part of the people in the laboratory.” But a sensitive conscience could reasonably disagree. Even if a person didn’t choose the vaccine’s research methods, she could still object to benefiting from the sale of fetal remains. A bishop and an average parishioner are equally qualified to judge the commercial entanglements of pharmaceutical enterprise with abortion; both must sift secondhand information.

The worldwide panic over COVID perhaps eclipsed bishops’ recognition of the supremacy of conscience. Discoveries about the epidemiology of COVID and the effects of the various medical efforts against it are constantly and rapidly developing. New information displaces what seemed known before, and all decisions risk practical error. But regardless of new data and scientific findings, we must always be careful to avoid moral error—and conscience is our primary guide in avoiding moral error. ‘“Conscience,’ says St. Thomas Aquinas, ‘is the practical judgment or dictate of reason, by which we judge what hic et nunc [here and now] is to be done as being good, or to be avoided as evil.’”

Coercion against the voice of individual conscience is equally forbidden to a pope and any other Christian. Individuals develop consciences under circumstances and obligations known only to themselves. Conscience must be heeded as “the voice of God,” St. John Henry Newman explains. No authority, even bishops, can properly countermand it. St. John Henry Newman said it well: “Conscience has rights because it has duties; . . . conscience is ever to be obeyed whether it tells truly or erroneously.”

The Church’s historic teaching is clear: if conscience forbids some specific action, it is forbidden. To betray conscience because of any pressure, secular or ecclesial, endangers one’s salvation. To tempt or coerce another to such a betrayal is a very grave matter. Newman wrote,

Conscience may come into collision with the word of a Pope, and is to be followed in spite of that word. . . . [T]hough it may suffer refraction in passing into the intellectual medium of each [person], it is not therefore so affected as to lose its character of being the Divine Law, but still has, as such, the prerogative of commanding obedience. . . . Hence it is never lawful to go against our conscience.

So, can every person decide which laws to obey? No; but he must resist a law that commands an unjust act. No Christian should tempt anyone to disobey his or her conscience and therefore sin.

Banning Exemption Letters

Yet ecclesiastics present their prudential judgments about vaccines’ moral permissibility as if they were divinely inspired Catholic dogma.

Blase Cardinal Cupich of Chicago wrote to priests on August 18, 2021 instructing them to “politely decline” requests for religious exemption, “and explain that doing so would mean that you would be endorsing something that is not in keeping with Catholic teaching,” according to a copy of the letter provided by WLS-TV. “Parishioners surely can determine their own actions, but it would be important to clarify that they cannot use the teaching of the church to justify such decisions, which in their essence, are a rejection of the church’s authentic moral teaching regarding Covid vaccines,” the cardinal wrote.

The cardinal’s letter does not sit well with the Church’s understanding of conscience. The Catechism of the Catholic Church clearly states the authentic moral teaching of the Church:

Man has the right to act in conscience and in freedom so as personally to make moral decisions. “He must not be forced to act contrary to his conscience. Nor must he be prevented from acting according to his conscience, especially in religious matters.”

and also:

Some rules apply in every case:
– One may never do evil so that good may result from it;
– the Golden Rule: “Whatever you wish that men would do to you, do so to them.”
– charity always proceeds by way of respect for one’s neighbor and his conscience: “Thus sinning against your brethren and wounding their conscience . . . you sin against Christ.” Therefore “it is right not to . . . do anything that makes your brother stumble.”

Theologians deem respect for conscience fundamental to the faith (de fide). It is essential to the argument of Vatican II in Dignitatis Humanae. Yet some bishops like Cupich have commanded priests to refuse to acknowledge in writing the sincerity of anyone convinced that, in his or her case, accepting the mandate is a sin. A priest need not agree with this conviction—he is merely a character witness. No priest should be obligated to write such a letter, but it is quite another thing to be obligated to refuse. It shames the petitioner, signaling that the very request is unfounded and unreasonable. Yet conscience, as the Church teaches, is the voice of God.

Double Effect

Some ecclesiastics, including Pope Francis, judge COVID vaccination a moral obligation because of the protection given to other people. Yet one is never obligated to cooperate—even remotely—in a moral abomination.

Nonetheless, formal casuistry does provide some ethical basis for bishops’ promotion of the vaccines: the principle of double effect allows material cooperation with evil for the sake of a good that outweighs it—if no ethical alternative exists. Bishop Athanasius Schneider compared accepting the vaccines tainted with fetal exploitation to permitting cannibalism in dire emergencies: neither is something to be encouraged but can be tolerated in extreme cases.

But, at the same time, the Church honors martyrs accepting torture or death in order to avoid condoning evil. In the biblical Book of Maccabees, the heroic Eleazar refused a governmentally required banquet serving forbidden meats—even when allowed to bring his own food—lest he give the impression of countenancing evil. He is celebrated for having accepted a grisly martyrdom instead. There are plenty of examples of holy men and women whose conscientious convictions exceed the ethical minimums the Church lays out.

The principle of double effect requires proportionality—a greater good—to outweigh cooperation with the undesired evil, and a dearth of other means for avoiding disaster. Doubts about the vaccines’ effectiveness and safety, whether founded well or ill, might confound someone’s confidence in proportionality. But even if proportionality is satisfied, the cooperation is only permissible, not meritorious. A Catholic might conclude that vaccination condones profiting from murder in order to protect people who could be protected in other ways. It’s also not clear that other means for avoiding disaster are unavailable. Effective vaccines can be developed from a number of less ethically problematic lines of cells, even cells from nonhuman sources; moreover, there also may be treatment and prevention options that have no violent origins.

There are plenty of examples of holy men and women whose conscientious convictions exceed the ethical minimums the Church lays out.


Conscientious Objection in War and Pandemic

In considering moral objections to the COVID vaccines, bishops should also recall the Catholic Church’s support for conscientious objections to participating in war. Participation in defensive war may be meritorious, but the Church has respected conscientious objection “[s]ince Apostolic times,” according to the USCCB, which even campaigned for “selective conscientious objectors to refuse—without fear of imprisonment or loss of citizenship—to serve in wars which they consider unjust or in branches of service (e.g., the strategic nuclear forces) which would subject them to the performance of actions contrary to deeply held moral convictions.”

Even in a defensive war, clergy are allowed to write letters attesting to the sincerity of the convictions of conscientious objectors. COVID is less dire than war, with a low case fatality ratio. Thus either culpable ignorance or more culpable dissimulation underlies this diocesan directive:

I will not issue, and I have directed our clergy not to issue, any Letters of Religious exemption because it would contradict the clear objective teaching of the Catholic Church and the Holy See on this matter.

It is dumbfounding that any bishop could contend that a Vatican official’s judgment about public health cancels the Church’s support for conscience rights dating from the papacy of St. Peter. The prestige of science sometimes wrongly intrudes on the proper ground of ethics. The cost of total ecclesiastical acceptance of CDC recommendations has been bitter: dismissal from employment, from military careers, from ministries—or, worse, the permanent stain of playing false to one’s relationship with God. It is a grave matter to tempt anyone to forfeit the soul’s integrity.

Church and Conscience

Psalm 146 says, “Put not thy trust in princes”—which must sometimes include Princes of the Church. Respect for the Sanhedrin did not keep St. Peter from preaching, nor did respect for civil authority stop him from leaving the jail when God opened the door. Citizens even have responsibilities to resist unjust government, especially in a democracy.

Some bishops, such as Archbishop Cordileone and Bishop Strickland, have issued statements in support of conscience rights. So have the bishops of Colorado, and bishops in South Dakota. Bishop Timothy Broglio of the Military Archdiocese issued a letter supporting sincere conscientious objection to the vaccines among military personnel. These men have acted with steadfast integrity, in the face of widespread scorn. Their faithfulness, in one sense ordinary, has become nearly heroic. Many other bishops have oppressed Catholics who refuse the mRNA injections, violating fundamental principles of Catholic morality. How many bishops actually hold that conscience is supreme? How many would sacrifice their flocks’ consciences out of fear for health—or lawsuits? How many for the sake of approbation from the powerful?

Is it fair that the faithful have to ask such questions? Is it fair to civil society—which a sensitive conscience might enlighten on an unpopular topic? If not in the Church, where else can the voice of a sensitive conscience find respect?