Step 1: Understanding the Question:
The question asks for the year of the first enactment of the Juvenile Justice Act at a national level in India.
Step 2: Detailed Explanation:
Before a unified national act, different states had their own Children's Acts.
1. The first comprehensive national legislation was the Juvenile Justice Act, 1986.
2. This was later replaced by the Juvenile Justice (Care and Protection of Children) Act, 2000 to comply with the UN Convention on the Rights of the Child.
3. The 2000 Act was further replaced by the Juvenile Justice Act, 2015 after the 2012 Delhi gang-rape case.
Since the question asks for the first enactment, we select 1986.
Step 3: Final Answer:
The Juvenile Justice Act was first enacted in India in 1986.