A topic on which there has been some, but not enough, written is that of complicity after the fact. A standard case is the question whether it is permissible to use the small amount of usable Nazi concentration camp medical "research" data (apparently some of the typhus and hypothermia data is useful). Is there any reason to avoid benefiting from the evils of others? I've made a distinction between two sorts of benefits: those benefits that the original evildoer intended, and other benefits. For instance, the Nazi camp doctors may have intended to benefit medical science. If so, then by using their data, one is "playing along" with their plan—one is, in some sense, complicit. It does not follow that the action is wrong, but it does follow that one has a reason (perhaps not conclusive) to refrain from it. On the other hand, the police officer who gets promoted for catching a criminal benefits from crime in a way that the criminal did not intend. This kind of benefiting from an evildoer's action is not a case of complicity, and there is no prima facie reason to refrain from it.
It has hit me that an exactly parallel issue comes up for benefiting from one's own past evil activity. If one has lied on one's resume and as a result got a job, then one's continuing to have the job is a way of benefiting from one's own past ill deed, and, moreover, the benefit is one that was intended by oneself when one lied. It seems to me that one can and should say very similar things about benefiting from one's own past evil deeds as about benefiting from others' evil deeds. In other words, when the benefit is not an intended one, and especially if it was not even hoped for or expected, one is not playing along, and one need have no qualms. For instance, when one benefits from one's past sins by becoming more humble through reflection on one's past weakness, that is not something one has any reason against. On the other hand, one does have prima facie reason not to continue in the job when one got it illicitly. Nonetheless, ultima facie, one might have reason to remain in the job—for instance, if one's employer could not replace one without significant loss to the employer (for instance, because one's employer has put significant effort into training one), one may have sufficient reason to continue in the job.
I think that the parallel between complicity in one's own past sins and in the past sins of others is illuminating and worth plumbing further.