Objectives: The article is an overview of developments in substantive criminal law in Nigeria in the last 53 years. It examines the sharing of constitutional legislative powers to enact criminal laws between the federal (national) government and the state (local) governments. The examination of federal laws revealed proactive legislative activity responding to emerging local and international criminal law issues. The main development at the state level is the introduction by States in Northern Nigeria of Sharia Penal Codes and the enactment of the Criminal Law of Lagos State 2011. A common trend is the entrenchment of death penalty as punishment for some crimes. Implications: While federal criminal laws have responded to emerging realties, state criminal laws have generally failed to respond to emerging issues at the state level. Consequently, in most of the southern states criminal laws introduced in 1916 have continued to apply. Value: The paper demonstrates the need for southern States to reform their criminal laws to respond to emerging realties, the federal government to respond to some outstanding criminal law issues and calls for a suspension of death penalty and a revaluation of its continued relevance.