Abetment (Section 107, Indian Penal Code, 1860):

Abetment refers to the act of instigating, engaging in a conspiracy for, or intentionally aiding the commission of an offence. A person is said to abet the doing of a thing who:

1. Instigates: Instigates any person to do that thing. Instigation means to incite, provoke, or encourage someone to commit an offence.
2. Engages in Conspiracy: Engages with one or more other person or persons in any conspiracy for the doing of that thing, if an act or illegal omission takes place in pursuance of that conspiracy, and in order to the doing of that thing. This form of abetment requires an overt act or illegal omission in furtherance of the conspiracy.
3. Intentionally Aids: Intentionally aids, by any act or illegal omission, the doing of that thing. Aiding implies facilitating or assisting in the commission of the offence.

The essence of abetment is the active complicity of a person in the commission of an offence, either by inciting, conspiring, or assisting. The abetted act does not necessarily have to be committed for abetment to be an offence in itself (e.g., instigation to murder is punishable even if murder is not committed).

Criminal Conspiracy (Section 120A, Indian Penal Code, 1860):

Criminal conspiracy occurs when two or more persons agree to do, or cause to be done:

1. An illegal act, or
2. An act which is not illegal by illegal means.

The core of criminal conspiracy is the agreement itself. The moment two or more persons agree to commit an illegal act or a legal act by illegal means, the offence of criminal conspiracy is complete. Unlike abetment by conspiracy (under Section 107), a separate overt act in furtherance of the agreement is generally not required to constitute the offence of criminal conspiracy under Section 120A, although such acts often exist and serve as evidence of the agreement.

Distinction between Abetment and Criminal Conspiracy:

1. Nature of the Offence:

   • Abetment: Focuses on the active role of a person in facilitating or inciting the commission of a specific offence. It is an accessory offence, linked to a principal offence.
   • Criminal Conspiracy: The agreement itself is the substantive offence. It is an independent offence, even if the agreed-upon act is not committed.

2. Overt Act Requirement:

   • Abetment by Conspiracy (Section 107, second clause): Requires an act or illegal omission to take place in pursuance of the conspiracy for the abetment to be complete.
   • Criminal Conspiracy (Section 120A): The mere agreement is sufficient to constitute the offence. An overt act is not a mandatory ingredient, though it often serves as proof of the agreement.

3. Scope:

   • Abetment: Can be by instigation, aiding, or conspiracy. It is a broader concept of participation in an offence.
   • Criminal Conspiracy: Is a specific type of agreement to commit an offence. Abetment by conspiracy is a specific form of abetment, which is a subset of the broader concept of criminal conspiracy.

4. Number of Persons:

   • Abetment: Can involve one abettor and one principal offender (e.g., A instigates B). Abetment by conspiracy requires at least two persons.
   • Criminal Conspiracy: Necessarily requires two or more persons to form an agreement.

In summary, while abetment by conspiracy is a form of abetment, criminal conspiracy is a distinct and independent offence where the agreement itself is punishable, even without any further act, provided the agreement is to do an illegal act or a legal act by illegal means.