Sometimes you can become too powerful or perhaps think you are more powerful than you really are.
In this situation it can be very easy to lose perspective on what is right and wrong. Getting the job done can appear to be more important than realising that the method by which you get the job done might actually have all the appearance of a lack of ethics and even, possibly, corruption.
The wise person usually keeps a perspective on what the limits of their powers are.
The unwise person distorts the truth, definitions and loses a sense of perspective of what is acceptable and what is not. They may even try to get measures passed that could return to embarrass someone who may not have agreed with them on other matters.
Even worse when they try to get measures passed which might significantly benefit their friends.
However, unwise person should realise that there are people in the wider society who are vigilant, who people come to when they feel that something is not right, and who they would rely upon to take action should sufficient evidence be gathered that strongly suggests wrongdoing. Those who believe themselves to have been wronged are very vigilant indeed and wait and watch.
There are eternal truths in society that the unwise person would do well to remember. Lord Acton's maxim should remind them of how to conduct themselves and to remind them that they should at all times be seen and act in a way which has the wider interests of the community they seek to serve at heart NOT their close friends. Otherwise they might leave an opportunity open for those previously wronged to avenge themselves.