A recent federal court case called for the deposition of Cardinal William J. Levada to answer questions about his handling of priests' sex abuse during his years as archbishop of Portland in Oregon (1986-95). In an unusual twist, the questioning placed under public scrutiny the age-old practice known in the Catholic tradition as mental reservation.

This practice suggests that in certain situations we can justifiably avoid telling the truth in order to serve a greater good. The victims' attorneys in the Portland case wanted to know whether Archbishop Levada would rely on the practice to protect the Church while he answered questions.

Some reporting on the case implied that mental reservation would permit the cardinal to lie. Is that true? To answer the question, and to explain the Church's teaching about mental reservation, we must first examine the nature of truth and its converse, the lie.

Truth and Truth Telling

Authoritative Catholic teaching holds that lying is intrinsically evil, although it recognizes that not every lie is a mortal sin. Unless a lie involves grave matter - for example, it causes serious scandal or harm to another person, or involves a denial of the Faith or perjury - it is a venial sin.

"By its very nature," the Catechism of the Catholic Church teaches, "lying is to be condemned" (no. 2485). It is prohibited by a moral absolute -namely, the Eighth Commandment: "You shall not bear false witness against your neighbor" (Ex 20:16; see also Dt 5:20; CCC, no. 2464). Consequently, no good reason or motive - even to achieve great good or avoid great harm - can justify lying.

Scripture in general testifies to the importance of truth and truth-telling. St. Paul tells us that "putting away falsehood, [we must] speak the truth, each one to his neighbor"(Eph 4:25; see also Col 3:9-10). The scriptural teaching on the subject can best be summarized by Jesus'words: "Let your 'Yes' mean 'Yes,'and your 'No' mean 'No.' Anything more is from the evil one" (Mt 5:37; see also Jas 5:12).

Two Definitions of a Lie

Jesus' absolute condemnation of lying seems to prohibit the kind of mental gymnastics often associated with practicing mental reservation. We are never to lie. But does mental reservation amount to lying?

To answer this question, we must first define lying. The Catechism says succinctly: "Lying consists in saying what is false with the intention of deceiving one's neighbor" (no. 2508). Despite this simple statement, there is a long historical debate about the actual meaning of the term.

Catholic moral theologian Germain Grisez has observed: "Although most Catholic theologians have considered the prohibition of lying a moral absolute, there is a lesser but significant school of thought holding that lying sometimes can be justified, particularly when it is a question of lying to an enemy, who has no right to the truth, in order to protect the innocent from harm" ("The Way of the Lord Jesus,"vol. 2, Franciscan Press, 1993).

These two ways of thinking are reflected in the editorial process of the Catechism, which was revised for the book's second edition. The earlier edition (1994) stated that to lie is "to speak or act against the truth in order to lead into error someone who has a right to know the truth" (no. 2483, emphasis added). This definition, reflecting what Grisez calls the "lesser but significant school of thought," stems from the teaching of the 17th-century Protestant writer Hugo Grotius.

After the publication of the Catechism, many Catholic scholars wrote to then-Cardinal Joseph Ratzinger (now Pope Benedict XVI) about this paragraph. They asked for rectification of the text, which had abandoned centuries of Catholic teaching by accepting the position of Grotius. Fortunately, the paragraph was revised; the 1997 edition eliminates the words "who has a right to know the truth" (see also no. 2484).

Defining Mental Reservation

The important issue of whether someone has "the right to know the truth" figured prominently in the development of the doctrine of mental reservation. Catholic theologians formulated it to deal with situations where we have a duty to protect a truth or a secret but seem hard-pressed to do so without deliberate deception - that is, a lie.

Some theologians, following Grotius, call this kind of deception a morally justified falsiloquium (a "necessary lie"), since, they say, it does not violate the other's right to the truth.

Consider this commonly cited scenario: Suppose you live in Nazi-era Germany, and the police ask you whether any Jews are hiding in your home. You are indeed hiding a Jewish family, but you must protect them. So how should you reply?

In such a dilemma, when silence or some other means would not suffice to rebuff the enemy, an answer can be given, according to moral theologian Benedict Ashley, O.P., "that is not contrary to what one knows, but which at the same time does not reveal what one knows because it is ambiguous and might mean several things. Such an ambiguous reply leaves the wrongful questioner uncertain about what is meant and liable to self-deception by jumping to unwarranted conclusions" ("Living the Truth in Love," Alba House, 1996).

Rather than speak of "mental reservation," Ashley prefers - rightly, in my view - to speak of an "ambiguous answer."

To illustrate: In reply to the question, "Are you hiding Jews in your home?" someone might reply, "Are you crazy? Don't you think I have my own family here to worry about? You're wasting your time. Go search somewhere else."

Such a reply, some might argue, contains no lies. Spoken with a convincing tone of annoyance, it might persuade the police to leave without involving the speaker in saying anything false.

When confronted with a similar example, however, St. Thomas Aquinas said we should reply, "I know where they are, but I will not say where." As John Finnis comments, we could think of "equally or more subtle responses [than that of Aquinas] which are yet free from all falsity of assertion." But if we actually lied to the Nazis, we would be entering "into [their] politics of manipulation."

By refusing both to lie and to violate our duty of nondisclosure, we affirm "the human dignity of everyone concerned, including even the Nazis, who have no right whatever to be given the answers they are demanding" ("Aquinas," Oxford University Press, 1998).

Strict vs. Broad Mental Reservation

As early as 1679 Pope Innocent XI condemned a version of mental reservation known as "strict" or "pure," as formulated by the 17th-century Jesuit Thomas Sanchez. In the strict sense, it means giving voice to only part of one's judgment while retaining in mind or whispering silently another part that makes the assertion objectively truthful.

For example, a student is asked by a teacher whether he cheated on an exam by copying Bob's test, and he replies: "No, I did not copy from Bob." The student knows, but doesn't say, that he actually cheated by copying from Ted's exam.

In the broad sense, mental reservation is "the use of equivocation or ambiguity to conceal the truth. What is said is not objectively untruthful, but it is phrased in such a way that it is possible, indeed probable, that the true meaning of the words will escape the hearer, and that he will understand them in a sense in which they are not true" (D. Hughes, "Mental Reservation," New Catholic Encyclopedia, 1967).

Grisez states that faithful Catholic authors who have accepted the practice of broad mental reservation have disagreed among themselves "on exactly what it is and how far it licitly extends." He rightly accepts a more restrictive version of mental reservation, one that is taken to mean "expressions which can obscure the truth even if no one is deceived, and so can be effective without expressing an assertion believed to be false."

For example, in our culture, the statement "Mr. Jones is not in the office" typically means that Jones is not taking phone calls right now (or, at least, not this particularphone call). The caller understands (or should understand) that this is a polite way of saying, "Jones is not available to you at this moment, even though he is actually in the office." No one is really fooled by this expression using ambiguous language; we simply take it for what it is.

Catholic Conscience and Mental Reservation

This much seems reasonable, then: A form of broad mental reservation (in the sense of ambiguous speech as understood by Grisez) -although difficult to employ for some - can be used in a morally good way under two conditions.

First, there is a just reason for doing so. Second, the inquirer has no right to the information. This approach, rather than false speech (lying), can honor the good of truth as well as the need to protect persons by hiding the truth through equivocal speech or, as Aquinas says in the Summa Theologica, "under some concealment."

Nevertheless, straightforwardness in speech must be considered obligatory under normal circumstances. And in the specific case with which we began - testimony in a court case - mental reservation would not be permitted, since courts require the full truth from witnesses.

In every case, as the authors of the adult catechism "The Teaching of Christ" note, a Catholic must carefully consider "what kinds of silence, or forthrightness, or evasive or partial response, would fairly serve all the interests rightly involved, and at the same time avoid any direct contradiction of what one judges to be the truth" (3rd ed., Our Sunday Visitor, 1991). Such is truth's great value!

Mark S. Latkovic, S.T.D., is a professor of moral theology at Sacred Heart Major Seminary, Detroit, Mich. He is co-editor, with John Goyette and Richard S. Meyers, of "St. Thomas Aquinas and the Natural Law Tradition: Contemporary Perspectives" (CUA Press, 2004) and a board member of the Fellowship of Catholic Scholars.