It is highly debatable whether to reduce crime by increasing prison duration or finding better ways. In my opinion, lengthening the prison duration can be a way to reduce a crime, but there are plenty of other options available to reduce crime. In the paragraph below both opinions would be discussed.
There is no contrasting view that increasing length of prison duration can reduce crime as prisoners are held inside the jail, it will reduce the contact of them with outside world, ultimately reducing chances of committing crimes. Additionally, it will capture them for high crime committing period. For instance, we have heard about person, who committed crime after getting bail from prison of Kathmandu in July 6.
On the contrast, instead of lengthening their prison duration, we can shift our focus on changing their attitude via religion, meditation, lectures etc. If we can instill good values and morality, they can contribute to the development of nation. Additionally, they can help other people to become a good citizen, describing the torture and guilt which they have Buddhist sculpture e to face due to crime. For example, in Buddhist sculpture there is a person named Ankulimala who committed lot of horrendous crime, but when Buddha enlighten him with knowledge; he started promoting good values, moral and ethics.
In a nutshell, we can shift our focus on improving ethical values of prisoners, it could lead to better society than lengthening sentence duration. Ultimately leading to high good of the society.