The Deuteronomy example and Texas jail example were just to highlight approaches to punishment. They are actually from a book called "The Puzzle of Ethics" by Peter Vardy and Paul Grosch. I am sorry I should have made that clear. It is a very open-ended book and doesn't lay out one philosophy. It does have religious overtones but I am not reading it for that purpose. It is just an overview of ethics so has everything from Kant, Mill, Plato to modern 19th century feminist philosophy as well as modern DNA theories. Anyway below are some of my personal views on the effectiveness or non-effectiveness of cultivating ethics.

Any change in a person is internal but there are moments when something external may bring about that change. A good example are people who have had near death illnesses or experiences whose previous behaviour can change literally to the opposite of what it was. Young soldiers who killed in a conflict may experience profound regret at their actions because of the birth of their child or the death of a parent.

Humans develop as they age and wisdom is just a word that describes the ethical changes a person undergoes as they age. If society is responsible for education then the State obviously finds it easier to inculcate young people into conforming to the State's political agenda which may or may not be ethical. As you age you develop a deeper understanding. Personally I am always suspicious of people who do not change and I describe this as "blocking". The people I have met who are blocked from changing are normally blocked by someone or something (usually parental rubbish) and I cannot strictly class them as agents with free-will.

Normally I delete my posts with zero votes or negative downvotes on the assumption that I have digressed from the original topic or I have made an error in my comment. This time I will leave the original comment and this reply.

So to keep on topic. Ethics is a lifetime study but not everyone will be able to follow a lifetime educational program due to "blocking". So ethics for all university graduates regardless of the course they choose would be desirable. Of course there are thousands of "blocked" university students but I would not want to be treated by a "blocked" doctor. I wonder how many operations have been deliberately bodged by a doctor who thinks he or she has the ethical right to do that to their patient because they may disagree with their patient's personal life, occupation or their behaviour while in hospital. It may be as simple as the doctor has heard a rumour that their patient is a paedophile when their patient is not a paedophile and the patient is completely unaware of the rumour and therefore is not in a position to defend themselves.

The problem with conformity is that it is too easy to persuade others of a load of rubbish. The problem of thinking that you do not need ethical training is that you don't develop the ethical tools to weigh the evidence if there is any evidence in the first place.

I agree with you that it is hard to change the ethical position of someone else but it is possible. Though it can only be the person themselves who makes the change. However you can try to guide others but as I said earlier some people have been blocked at a very early age. If being blocked helps them to navigate life then there is very little you can do. The point I made about doctors is very real and the ethical training they receive does not lessen the fact that they are just human beings with flaws.