由於日本刑法對於犯罪做概括規定，並使法定刑的幅度寬廣(舉例而言，殺人罪僅於刑法中一個條文規定「殺人者，處死刑、無期徒刑或五年以上懲役。」)從而法官於審判時，得依具體個案詳細檢討犯罪情事與案件內容，以作為量刑之判斷。如此一來，輕犯罪的概念在刑法上即不具重大的意義，而是在審判的運用面上顯得重要。當然輕微犯罪在刑法上是有些許處罰規定的，在刑法以外的特別刑法中更是所在多有。舉例而言，輕犯罪法與迷惑防止條例即為是例。據此，由於侵害法益的程度甚微，將刑法所不處罰然而該當的利益侵害行為予以犯罪化，處罰的空隙可能被填補。將被害法益輕微之行為予以可罰化時，在考慮維持國民生活安全及穩定治安的同時，另一方面也應兼顧須避免過度處罰所形成不必要的犯罪人。

Japanese Penal Code provides offenses comprehensively and has a wide range of statutory penalties, for example murder is punished with only one clause, “A person who kills another shall be punished by the death penalty or imprisonment with work for life or for a definite term of not less than five years.” Judges judge sentences – what type of punishment the accused receives or/and how long he stays in a penal institution - by considering criminal circumstances and cases in detail and carefully at trials. It could be declared that the concept of minor offenses is not very significant and that it is more important how to apply laws at practical trials well. In addition to several clauses for minor offenses in Penal Code, there are more clauses in special penal codes, for example Minor Offense Act and Anti-Nuisance Ordinance. These codes criminalize invasive acts that are not punished in Penal Code because the degree of the protection of their legal interests is trivial, so that gaps between punishment and non-punishment are filled. It is true that it contributes to keeping public safety and social order to criminalize invasive acts, but excessive punishment could lead to increasing offenders unnecessarily. The purpose of criminal treatment is to improve and rehabilitate offenders, to make them return to society and to prevent their repeating offenses. The number of the recognition of offenses was increasing till 2002 and is decreasing afterwards. Consequently, sentenced persons were increasing and are decreasing afterwards. It is due to a great deal of efforts of police, penal institution and so on in order to reduce offenses. Some facts must be admitted, however, that there are still a lot of repeating offenders, that offenders of advanced age are increasing year by year, and that excessive commitment to penal institution is not settled enough. These problems consisting in intramural treatment must be solved sufficiently. Some propose new kinds of treatments as using non-governmental sectors that we can see in private penal institutions and some propose to use extramural treatment as parole and probation more. We must keep in mind that issues in criminal treatment cannot be solved only in criminal policy but also in cooperation with many fields as economic and social policy and so on.