This is one of those questions that seem easy to answer, but the more one ponders over it, the harder it becomes.
In most nations when a minor commits a crime, his or her record can always be wiped off when they grow up. The rationale of this rule is that the youth are still in their development and learning stage. Their mistakes are sometimes very severe but the system gives them an opportunity to begin afresh rather than bearing the burden of the mistake throughout their lives.
I myself see the reason of this rule.
When individuals are young, they may do things without thinking over them. A teenager may act in a reckless way due to peer pressure, anger or just because he or she does not know entirely the consequences of their actions. Life experience can teach us a lot and many people turn out to be totally different people when they become older.

Then in that respect, it is rational to provide someone with a second chance.
The case is worse when one considers the same situation but on the other side being the side of the victim.
Once one has committed a crime, its impact does not simply fade away with time. In case a person was harmed, robbed, or traumatized, these experiences may remain with him or her over the years. In the eyes of the victim, it may be unjust that the individual responsible can just get away with a clean sheet whilst they continue to face the aftermath of the situation.
This is why I do not believe that this problem can be resolved by using the same rule and applying it to all cases.
All crimes are not equal.
There is a large gap between the foolish decision of a teenager, such as robbing something small, and a minor committing a serious violent crime. In the former situation, it is reasonable to leave the person to develop and learn a lesson and then continue with his life without that record trailing him/her all life long.
However, when the offense is grave and the damage is severe it would be more difficult to explain why it is necessary to clean up the slate.
The other thing that I tend to consider is how environments affect young people. Certain minors are brought up in extremely challenging circumstances, such as poverty, broken families, or criminal neighborhoods. There are cases when it becomes hard to draw the line between bad choices and survival in such circumstances.
That is no excuse to avoid crime but it does imply that rehabilitation is to be considered as a significant part of the justice system. Provided a young person actually reforms and strives to create a better life, the society must be ready to give them an opportunity to show that they are not the individual they were a few years earlier.
Meanwhile, accountability does not lose its significance.
A system, which entirely overlooks the harm inflicted on victims, would be unjust too.
In my case, a middle way is most likely to be the most effective. Small offenses must have a way to clear records once they have indeed been well reformed and more serious crimes should be approached with more caution and care.
Justice should not only focus on punishment, but it should also focus on growth and rehabilitation. Human beings can change, particularly when they are not very old.
That second opportunity must however be accompanied by reflection, responsibility and understanding of the effects their actions had on others.

I totally agree with you on this... Everyone deserves a second chance.
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