Sometimes people cooperate with a person doing evil by approving what the person does, or by willfully and knowingly partaking in the evil action…. This is formal cooperation in an unethical act, and it is always wrong. Conversely, I may cooperate with another person, not because I freely approve or cooperate in the evil action, but because I am coerced into cooperating…. When the duress is present, the cooperation is known as material cooperation, and it may be of two different kinds. If one cooperates in an evil act by performing something that is essential for the performance of the evil action, then it is immediate material cooperation. If one cooperates in an accidental or nonessential manner in the evil action, then it is called mediate material cooperation.
For example, if one works at an abortion clinic only because one needs a job to support one’s family, this is material cooperation. But the type of material cooperation will depend upon the manner in which the person cooperates with the person responsible for the evil action. If one operates the vacuum machine that aborts young fetuses, one is doing something that is essential for performing the evil of abortion. Thus, it would be immediate material cooperation. Immediate material cooperation in the evil act of another is not ethical, even if there is duress present.
However, if one nurses people after they have had abortions, or cuts the grass at the abortion clinic, it would not contribute anything essential to the act of abortion and would be an act of mediate material cooperation. Finally, the possibility of scandal could prohibit acts of even mediate material cooperation because, even though the moral object of the act is good, it may lead another into sin.
