In the Canon Law of the Catholic Church, a canonical impediment is a legal obstacle that prevents a sacrament from being performed validly and/or licitly. The term is used most frequently in relationship to the sacraments of Marriage and Holy Orders. Some canonical impediments can be dispensed by the competent authority (usually the local ordinary) as defined in Canon Law.
Impediments to marriage
Roman Catholic sacramental theology teaches that the ministers of the sacrament of holy matrimony are the man and woman, and therefore any marriage contracted voluntarily between two baptized and unmarried adults is valid, though under ordinary circumstances the marriage must be blessed by a priest to be licit. However, various provisions in current canon law lay down additional requirements for validity, in apparent contradiction of this principle.
Impediments to marriage are classified according to many different criteria.
In regard to their effect on the sacrament, impediments are either diriment, which invalidate an attempted marriage, or prohibitive (or impedient), which make a marriage illicit but valid. The 1983 Code of Canon Law does not contain prohibitive impediments as such, and thus the distinction between validity and licitness is less clear than in previous formularies.
In regard to their origin, impediments are either from divine law, and so cannot be dispensed, or from ecclesiastical law, and so can be dispensed by the competent Church authority. Under the 1983 Code of Canon Law, ecclesiastical impediments only apply to marriages where one or both of the parties is Catholic. Under the prior 1917 Code, ecclesiastical impediments applied to the marriages of non-Catholic Christians as well, unless specifically exempted. Note that, as clarified by articles 2 and 4 of Dignitas Connubii, the Catholic Church now recognizes the diriment impediments of other (i.e., non-Catholic) Churches and ecclesial communities when their members are parties to a marriage.
Impediments are also classified as follows:
- public, which can be proved in the external forum, or occult, which cannot be so proved;
- absolute, which apply to one party regardless of the other party, or relative, which apply only in relation to certain other parties;
- permanent or temporary, according to the duration of the impediment; and
- (for ecclesiastical impediments) whether they can be dispensed by the local ordinary under ordinary circumstances, or whether their dispensation is reserved to the Pope
List of diriment impediments to marriage
- Age. If the man is under 16 years of age, or the woman is under 14 years of age, then their marriage is invalid. This is an ecclesiastical impediment, and so does not apply to a marriage between two non-Catholics. However, note that in a marriage between a Catholic and a non-Catholic, the age limitation applies to the non-Catholic party as well. Each national episcopal conference has the authority to set a higher minimum age as a prohibitive impediment. Note that, in general, individual bishops do not have this authority (cf. CIC c. 1075 §2). In Canada, and also in New Zealand, this minimum age has been set to 18 years old for both parties. In England and Wales, this minimum age has been set to be in accordance with civil law (i.e., 16 years old for both parties). In Gambia, Liberia, and Sierre Leone, this minimum age has been set to 18 years old for the man and 16 years old for the woman. In the Philippines, this minimum has been set to 20 years old for the bridegroom, and 18 years old for the bride. In South Africa, and also in Switzerland, this minimum age has been set to be in accordance with civil law. In Nigeria, the episcopal conference has delegated the authority to set a higher prohibitive minimum age to the individual bishops. The United States Conference of Catholic Bishops has not enacted a higher prohibitive minimum age for marriage.
- Physical capacity for consummation lacking . Per Canon 1084 §3 "Without prejudice to the provisions of Canon 1098, sterility neither forbids nor invalidates a marriage." Both parties, however, must be physically capable of completed vaginal intercourse, wherein the man ejaculates "true semen" into the woman's vagina. (See  for details.) To invalidate a marriage, the impotence must be perpetual (i.e., incurable) and antecedent to the marriage. The impotence can either be absolute or relative. This impediment is generally considered to derive from divine natural law, and so cannot be dispensed. The reason behind this impediment is explained in the Summa Theologica: “In marriage there is a contract whereby one is bound to pay the other the marital debt: wherefore just as in other contracts, the bond is unfitting if a person bind himself to what he cannot give or do, so the marriage contract is unfitting, if it be made by one who cannot pay the marital debt.”
- Previous marriage . Previous marriages, whether conducted in the Catholic Church, in another church, or by the State. All previous attempts at marriage by both parties wishing to marry must be declared null prior to a wedding in the Catholic Church, without regard to the religion of the party previously married. Divine, absolute, temporary.
- Disparity of cult . A marriage between a Catholic and a non-baptized person is invalid, unless this impediment is dispensed by the local ordinary. Ecclesiastical, relative.
- Sacred orders . One of the parties has received sacred orders. Ecclesiastical, absolute, permanent (unless dispensed by the Apostolic See).
- Perpetual vow of chastity . One of the parties has made a public perpetual vow of chastity. Ecclesiastical, absolute, permanent (unless dispensed by the Apostolic See).
- Abduction . One of the parties, usually the woman, has been abducted with the view of contracting marriage. Ecclesiastical, temporary.
- Crimen . One or both of the parties have brought about the death of a spouse with the view of entering marriage with each other. Ecclesiastical, relative, permanent (unless dispensed by the Apostolic See).
- Consanguinity . The parties are closely related by blood. Ecclesiastical or divine, depending on the degree of relationship. Relative, permanent.
- Affinity . The parties are related by marriage in a prohibited degree. Ecclesiastical, relative, permanent.
- Public propriety . The parties are "related" by notorious concubinage. Ecclesiastical, relative, permanent.
- Spiritual relationship . One of the parties is the godparent of the other. This no longer applies in the Latin Rite, but still applies in the Eastern Catholic Churches.
Other factors which invalidate marriage
- Lack of form. When a marriage of a catholic takes place without following the laws and rites of the Catholic Church.
- Coercion. This impediment exists if one of the parties is pressured by any circumstances to enter into marriage. (In order for the impediment to cease, the situation must change so that the party can marry freely of his or her own will.)
- Psychological immaturity or mental incapacity To enter into sacramental marriage, both parties must understand and have the capacity to accept all that it entails.
- Refusal to have children One of the goods of marriage is children. A man or woman physically capable of fathering or, respectively, conceiving a child but who intends never to have children may not marry in the Catholic Church.
- Intention of fidelity lacking. Fidelity of each party to the other is a good of marriage. If this intent is lacking in either party, the couple may not marry in the Catholic Church.
- Civil Law. The Church recognizes the restrictions of civil law on marriage. If one of the parties is younger than the legal age for marriage according to civil law, the marriage may not take place in the Catholic Church.
Impediments to ordination to the Priesthood
Impediments to the priesthood are divided into "irregularities", which are permanent unless removed by the competent authority and "simple impediments" which may pass with time without action of an ecclesiastical authority. Canon Law also lists various impediments to the exercise of a priesthood that has already been conferred. The bishop can remove most irregularities and simple impediments, except for those involving public apostasy, heresy, or schism; abortion or murder, even if in secret; and existing marriages. Irregularities that cannot be removed by the bishop can be removed by the Holy See.
- Mental illness that prevents fulfillment of the duties of the priesthood.
- Physical incapacity to perform the rites of the Church. A priest must have his hands to celebrate the sacraments. He must also be able to ingest the wheat host and the wine. (A complete gluten intolerance, for example, is an impediment).
- Apostasy, heresy or schism. Previous rejection of the faith which was public and notorious is an impediment.
- Attempted Marriage. The attempt to marry despite an existing valid marriage or vow of chastity, or the marriage to a woman who had an existing valid marriage or vow of chastity forms an irregularity even after the death of the spouse.
- Participation in an abortion or murder. Any prior act, statement, financial or moral support which contributed positively to a specific case of successful abortion or murder is an impediment. This could include driving a woman to the abortion clinic or paying for her abortion. Paying taxes to a state that funds abortions would generally not be considered a "positive" contribution to the abortion.
- Attempted suicide, self mutilation, or mutilation of others. Any premeditated attempt at suicide disqualifies one as a candidate for ordination. The act of mutilation must be performed "graviter et dolose" in order for it to be an impediment (cutting off a hand or foot, castration, etc.) 
- Attempt to perform an act proper to the priesthood or episcopate. This applies to hearing acts such as hearing confessions, presiding at marriages, etc. when one has not received the proper ordination to do so.
Simple impediments to ordination
- Previous marriage. This applies to Latin Rite priests and bishops and Eastern Catholic bishops only. All previous marriages must be declared null, or the spouse must have died. In the case of a deceased spouse, most bishops require that the children be raised to adulthood before the man can undertake a vocation to the priesthood.
- Political office or other positions that a priest is not permitted to occupy. This impediment disappears as soon as the candidate is no longer in office.
- Recent baptism. The bishop must determine when a newly baptized person is sufficiently mature in his faith to undertake an ordained ministry in the Church.
Irregularities to the exercise of the priesthood
- Reception of ordination with an irregularity. If the irregularity is not brought to the bishop's attention before ordination, a priest might be ordained who has an irregularity. Such a priest cannot exercise his ministry until the irregularity is removed.
- Apostasy, heresy or schism that occurs after ordination, if this act is publicly known.
- Commission of acts that would have led to an irregularity.
Simple impediments to the exercise of the priesthood
- Reception of ordination with a simple impediment.
- Physical or mental illness that prevents fulfillment of the duties of the priesthood, until the bishop determines that the priest may resume the exercise of his ministry.
- 1983 Code of Canon Law for the Latin Rite (CIC)
- 1990 Code of Canon Law for the Eastern Rites (CCEO)
- Dignitas Connubii (Instruction to be Observed by Diocesan and Interdiocesan Tribunals in Handling Causes of the Nullity of Marriage), Pontifical Council for Legislative Texts, Libreria Editrice Vaticana, 2005. ISBN 88-209-7681-1.
- New Commentary on the Code of Canon Law, ed. by John P. Beal, James A. Coriden, and Thomas J. Green, Paulist Press, 2000. ISBN 0-8091-0502-0 (hardback). ISBN 0-8091-4066-7 (paperback, 2002).
- Code of Canon Law Annotated, ed. by Ernest Caparros, Michel Thériault, and Jean Thorn, 2004. ISBN 2-89127-629-9 (Wilson & Lafleur). ISBN 1-890177-44-X (Midwest Theological Forum).
- The Canon Law of Marriage and the Family, by John McAreavey, Four Courts Press, 1997. ISBN 1-85182-356-5.
- The Invalid Marriage, by Lawrence G. Wrenn, Canon Law Society of America, 1998. ISBN 0-943616-78-6.
- Canon Law: A Text and Commentary, by T. Lincoln Bouscaren and Adam C. Ellis, Bruce Publishing Company, four editions. Deals with the 1917 Code of Canon Law.
- Nullity of Marriage, second edition, by Frank J. Sheed, Sheed & Ward, 1959. Deals with the 1917 Code of Canon Law.  .
- ↑ Note: In the following, canonical references to the 1983 Code of Canon Law are denoted by "CIC", canonical references to the 1917 Code of Canon Law are denoted by "1917 CIC", and canonical references to the 1990 Code of Canon Law for the Eastern Churches are denoted by "CCEO".
- ↑ 1917 CIC c. 1036
- ↑ cf. CCEO cc. 780 and 781
- ↑ see CIC c. 1074, CCEO c. 791
- ↑ CIC c. 1078, CCEO c. 795)
- ↑ CIC c. 1083, CCEO c. 800
- ↑ New Commentary, Beal, et al., p. 1284.
- ↑ New Commentary, Beal, et al., p. 1284.
- ↑ Canon Law Annotated, Caparros, et al., pp. 1669 and 1717.
- ↑ Canon Law Annotated, Caparros, et al., p. 1677, and Canon Law Digest, v. 11 (1983-1985), p. 263.
- ↑ Canon Law Annotated, Caparros, et al., p. 1689.
- ↑ Canon Law Annotated, Caparros, et al., p. 1762, and Canon Law Digest, v. 11 (1983-1985), p. 264.
- ↑ Canon Law Annotated, Caparros, et al., p. 1783 (for South Africa), and Canon Law Digest, v. 11 (1983-1985), p. 265 (for Switzerland).
- ↑ Canon Law Annotated, Caparros, et al., p. 1741.
- ↑ See the USCCB website for the list of complementary norms that have been enacted.
- ↑ CIC c. 1084, CCEO c. 801
- ↑ New Commentary, Beal, et al., p. 1286.
- ↑ Summa Theologica, Supplement to the Third Part, question 58, article 1.
- ↑ CIC c. 1085, CCEO c. 802
- ↑ CIC c. 1086, CCEO c. 803
- ↑ CIC c. 1087, CCEO c. 804
- ↑ CIC c. 1088, CCEO c. 805
- ↑ CIC c. 1089, CCEO c. 806
- ↑ CIC c. 1090, CCEO c. 807
- ↑ CIC c. 1091, CCEO c. 808
- ↑ CIC c. 1092, CCEO c. 809
- ↑ CIC c. 1093, CCEO c. 810
- ↑ CIC c. 1094, CCEO c. 812. See also "Canonical Adoption". Catholic Encyclopedia. New York: Robert Appleton Company. 1913. http://en.wikisource.org/wiki/Catholic_Encyclopedia_(1913)/Canonical_Adoption.
- ↑ CCEO c. 811, also see 1917 CIC c. 1079
- ↑ 30.0 30.1 Can. 1041, 1°
- ↑ Can. 1041, 2°
- ↑ Can. 1041, 3°
- ↑ Can. 1041, 4°
- ↑ Can. 1041, 5°
- ↑ Can. 1041, 6°
- ↑ Can. 1042, 1°
- ↑ Can. 1042, 2°
- ↑ Can. 1042, 3°
- ↑ Can. 1044 §1, 1°
- ↑ Can. 1044 §1, 2°
- ↑ Can. 1044 §1, 3°
- ↑ Can. 1044 §2, 1°
- ↑ Can. 1044 §2, 2°