This show would better be entitled the immorality of revenge. Your lawyer is saying justice and revenge are the same thing. I couldn't disagree more. YThe show demonstrated zero understanding of the unjust conditions that underly perpetration in many cases. Those are unjust conditions. Victims should not decide what happens to perpetrators. Often victims are indeed part of the dynamic. Not always. But sometimes. Your speaker lacks a sense of justice because he is so keen on revenge. I believe the desire for revenge should not be indulged.

There are four reasons for punishment/incarceration. Somehow, they missed protection of society as one of the principal reasons. An individual who has committed a crime worthy of incarceration, is one who shows either a desire to cause harm or a callous indifference/negligence to the harm his acts cause. Which makes him likely to repeat. Incarcerating is a way of society choosing to defend itself.
John believes that the reason the US went after and killed bin Laden was revenge. Seriously? He and the movement that he began, had orchestrated and plotted attacks from 1993 onward, on several continents: World Trade Center (1993), US embassies in Africa, 9/11, Madrid, London, Bali, ... Several other attacks had failed. The idea that killing bin Laden was solely or even primarily out of revenge strains credulity considerably.
Another reason, deterrence, is quite powerful. The problem with eye-for-an-eye or commensurate punishment is that, unless the perpetrator believes with certainty that he would be caught, commensurate punishment cannot deter. If I could steal $100,000 and at worst have to repay the $100,000, then why not do it? I'd have nothing to lose, and $100,000 to gain! Granted there is no credible evidence that the death penalty is a deterrent to murder compared with life-imprisonment, but only naivete could allow one to conclude that would-be criminals do not weigh potential incarceration.
Additionally, in criminal proceedings, the victim (or the victim's family) can become a witness, only insofar as he has something material to contribute -- material in the determination of guilty or not guilty. Otherwise, to describe the extent of the harm incites emotions in the jurors, who ought to render their judgements dispassionately. Once found guilty, then victims and their families can testify, in the sentencing phase.
Emotional decisions can too easily compound one injustice, the harm caused to the victim, with a second injustice, a wrongful conviction, because jurors will be more likely to want to search for someone to blame.
Lastly, the guest's argument seems to be that since vengeance feels good and is natural, it is moral. Yet monogamy is rare in Nature and for many does not feel good; theft feels good and is natural, particularly when the perpetrator can "get away with it." I thought that the very idea of morality, the development of moral codes, is to rise above what is natural, what does not need to be taught or instilled.

I felt that the guest came dangerously close to endorsing subjective justice - because you felt that you were wronged, you have the right to seek justice against the person you deem to be the perpetrator. The example he gave was extreme - the murderer of a child who used legal loopholes to receive a reduced sentence for his crime. What about less clear circumstances, when guilt hasn't been admitted, when the crime isn't as heinous? Few things seem as dangerous to me as permitting subjective justice. There's no process in it, no reason, no evaluation of the evidence. It's lawless.
On a completely different note, I really disliked that the guest said of a caller, "I'm sure she's lovely, but [her ideas are ridiculous]." I thought it was rude and dismissive. There are more respectful ways of disagreeing.

I think we have to differentiate revenge first. As the name and description implies, it is a premeditated action to return the pain that was inflicted. In nature, when a tiger bites your leg of after you've poked it with a stick, we do not call it revenge, instead it is normal behavior for the animal in question: it simply defends it's own territory and it's own life. Assuming animals do not have higher thinking -like humans and other primates- this causal relationship is almost automatic. Now when applied to humans, we can say the same. When someone attacks you, the autonomous nervous system has only two choices:
1) release adrenaline to the muscles and prepare to run.
2) release adrenaline to the muscles and get ready to fight.
Still, we are human and we are capable of higher thinking. We can basically override our basic instincts, we can master our bodily responses. So we can choose to defuse the situation for our own best interest, because every fight has victims on both sides. We can look into the future, and we can predict that we might get hurt, die or will be arrested if we lose our cool. But then the question arises: what is this emotion that we call revenge? especially after the situation that took place has past. I think it has to do with our ego and the need to take action upon inflicted pain.
The choice of fight or flight did not satisfy us, and in the act our ego might be bruised. Others have witness our shame, our guilt and dehumanization and the infliction of pain. Since humans are social animals, and do have a kind of caste system or pecking order, the social degradation in a certain situation makes want to restore our former social position. And so basic territorial behavior comes back into play. We can either let it go, and possibly satisfy yourself with a lower social ranking, or take the action of revenge to reclaim our social position. The paradox in this, is that by the act of taking revenge, we might even get further down the social ladder. On the other hand, we also might be seen as strong leaders. In any event, it is a highly complex emotion.

I appreciate higher thinking as much as the next homo sapient. This evening, though, I encountered a paradigm not previously known. A person new to my realm of experience was speaking of something called a Canadian Tuxedo party. Had never heard of this. Seems people show up, dressed head-to-toe in denim, and do whatever else they may do to denigrate Canada and Canadian culture. Jane (not her real name) is around thirty-five years of age. I asked her what she knew about Canada. She admitted not much. I asked her what she thought about such tuxedo parties. Her response was, well, it was what we did. And so, here we go and there we are...oh, by the way, Canadian tuxedos look pretty much like American tuxedos. Unless someone wants something different.

Forgiveness is powerful? I must admit I had not heard that before. Many years ago (well, more than ten and less than twenty), I attended an employer-sponsored, week-long training session in Maryland. The training was conducted by notables from notable university environs. The subject: mediation. During the week, one instructor brought forth the notion that APOLOGY was a powerful tool in mediating disputes. I suppose so, but never really got to find out, because after that training and expenditure of state money, I was never afforded the opportunity to exercise the skills gained: Trained to be a mediator but never given the opportunity to develop that skill set. Never did figure that one out. So, are apology and forgiveness the same? Well, they may be close cousins in intention, but neither are worth spit when their application is mere façade. Ethically, 21st century homo sapiens is mostly bankrupt, in my view. You may quote me, if you wish. The notion is not new.(After thought: The political jackass who sent me to mediation training lost his job, only to be promoted to another political jackass position---hmmph.)