Internal security means security within the territorial borders of a sovereign state and compliance to various national and state laws enacted for the maintenance of law and order within the boundaries of a sovereign state. This clearly means that internal security encompasses law and order. That is the reason that the framers of the Constitution bestowed the responsibility for maintenance of law and order to state governments.

As per the seventh schedule of the Article 246 List-I, that is the Union list, the defence of India, deployment of any armed forces of the union falls under the domain of the Union government. Public order and the police fall under List-II, that is the state list, and is the exclusive domain of state governments. Internal security is within the state domain only until the state police exclusively maintain public order. A state requisitioning central armed police forces to tackle a situation is an indication that the police lack the capability to handle the situation.

It could also be taken as acceptance of the collapse of public order leading to an internal security situation with wider national security ramifications. That is the reason the ministry of home affairs (MHA) has its own definitions of internal security wherein every collapse of public order may not be an internal security issue requiring direct involvement of the MHA despite the fact that central armed police forces (CAPFs) have been requisitioned in aid of civil power. As per para 2.1 of the annual MHA report for 2021-2022, internal security issues in the country can broadly be categorised as terrorism in the hinterland of the country, left wing extremism (LWE) in certain areas, insurgency in the north eastern states and cross-border terrorism in Jammu & Kashmir.

If the internal security situation is analysed, large parts of the country face security challenges leading to the deployment of CAPFs, although it is a fact that CAPFs are called every now and then citing police inability to deal with a situation. During elections the CAPFs are placed at the disposal of the election commission. Therefore, the election process can also be categorised as an internal security situation as the state law and order machinery is incapable if conducting elections in a free and fair manner. The CAPFs comprise internal security and border guarding forces such as the BSF, CISF, CRPF, ITBP and the SSB, with a combined strength of more than a million. They are a major resource at the disposal of the union government to deal with internal security problems. Considering the volatile security scenario existing in various parts of country, the CAPFs are called in aid of civil power to ensure peace as the state law and order machinery is unable to deal with the situation. Keeping the volatility of situation in mind, the Rapid Action Force (RAF), a specialised force for handling law and order problems, came into existence in 1992 to provide an instant response during riotous situations in general and communal or sectarian conflicts in particular. These battalions are located in highly sensitive locations across the country to facilitate quick response and to control a potential flare-up. But despite the deployment of the CRPF and the RAF, there is still a need to deploy border-guarding CAPFs to meet the shortfall in the security grid.