Assisting in another's wrongdoing without approving it. The help given assists a person to perform the sinful action, although of itself the help is not wrong. To provide necessary information to a thief, because one is forced to, would be material co-operation. Material co-operation with another person's evil action is allowed provided certain conditions are fulfilled. Such collaboration is licit because the co-operator does not internally approve of the sin of another, nor does he or she approve of the sinful use to which the assistance is put by the other. The following principles are standard in resolving this complex moral issue:
Two kinds of material co-operation are to be distinguished: immediate and mediate.
In immediate material co-operation, one person actually does something morally wrong with another person. Thus if a surgeon and an assistant are both engaged in actually aborting a fetus, the co-operation of the assistant is immediate. Immediate material co-operation in the sinful act of another is always wrong. It is pointless to say that a person who is not under duress performs a criminal action without intending to do so.
Mediate material co-operation is concurring in the wrong action of another, but not in such a way that one actually performs the act with the other or agrees with the evil intention of the other. While doing something that is in itself good or indifferent, a person rather gives an occasion to another's sin, or contributes something by way of assistance.
The morality of mediate material co-operation is to be judged on the principle of the double effect. In applying this principle, there are four basic norms to be observed. Among these norms is the obligation not to intend the evil effect (as would really be intended in immediate material co-operation) and the need for sufficient reason to permit the evil effect. The presence of a proportionate reason is not sufficient to allow what is called material co-operation.See Also: DOUBLE EFFECT