The fact that internal and domestic spy agencies of the same government—and sometimes of the same department—do not share information is due to interdepartmental rivalry, rather than technical limitations. If the government really wants to, it can even today easily arrest the IAS officer from Bangalore who goes to China regularly without permission by flying via Calcutta. It does not, though the government not only has all the information in the customs and immigration database but also other electronic surveillance systems such as Crime and Criminal Tracking Network & Systems Project (CCTNS Project), National Intelligence Grid (NATGRID), National Counter Terrorism Centre (NCTC) of India in a total of 21 known databases. Not using the information available in one database will only lead to more confusion when 21 databases are interlinked.
Sharing of information, and mining of such voluminous data would ultimately be in the same league as other electronic surveillance with the same results: most often it is used for political purposes, for the security of the party in power. In times when there is no political crisis, it is used by the bored eavesdroppers to listen in on romantic interludes… intercepted calls of the wives of MPs discussing personal and sensitive matters, corporate leaders seeking private liaisons in hotels, corporate leader seeking a woman… calls at night are for sex… a woman official of DRDO near the Nizamuddin bridge area discussing some very personal liaisons—in short as a public funded porn telephone. Having bored publicly funded ‘data analysts’ ogling online porn is that last thing that we should encourage. Perhaps NTRO operatives would differ, and consider it perk.
The more important reason is that some data must always be kept separate, even within the security agencies, to prevent misuse and paradoxically, to enhance security. It is for precisely this reason that the Cabinet Committee on Security (CCS) did not permit the interlinking of the databases to form NATGRID in early 2010—not because they care about civil liberties, but because they realised that they may not always be in government, and then the database could be used against them.