The principle of double effect is a set of ethical criteria for evaluating the permissibility of acting when one’s otherwise legitimate act (for example, relieving a terminally ill patient’s pain) will also cause an effect one would normally be obliged to avoid (for example, the patient’s death.)
-
The act itself must be good
-
The bad effect cannot be the means to good
-
You must have a good intention. The bad bit must be a side-effect.
-
Total good must be greater than total bad.