Air India overbooks - carried more passengers than capacity

Airlines frequently overbook, given that there is always a number of people who will cancel, and hence there is a mathematics related to the number of people who overbook. Sometimes airlines land up in a situation whereby they find that this mathematics goes awry, and they find that there are more passengers than seats available. In such cases, the airline has to placate irate passengers, and decide who can go and who needs to be refused. Such cases typically cause a lot of unhappiness. However, it is not accepted that an airline boards more passengers than there are seats available. Even in these bad economic times, it is unacceptable to have more passengers on board than there are seats, given that these are paying passengers who have a right to proper treatment. Modern airlines have automated systems whereby boarding passes are issued which prevents extra passengers from getting loaded. However, if the airline wishes to violate such conditions, there is very little that can be done.
Further, after the terrorist incidents, the cockpits of planes are now high security zones where passengers are no longer allowed. So, if there is a case when a passenger is allowed inside the cockpit, that is against all security norms and needs to be thoroughly investigated.
We have a case, whereby all this happened. Air India, the national carrier of India, had a case whereby it was found that the airline had boarded 3 extra passengers; this case is now being investigated by the regulator, the Directorate General of Civil Aviation (DGCA). In order to ensure that this case is brought to its logical conclusion, the investigation needs to be thorough (link to article):

In these recessionary times, airlines globally are operating on half-empty seats. But Air India, which is passing through its worst ever financial crisis, is in fresh trouble for allegedly carrying extra passengers on a fully loaded flight. What adds to the irony is that the excess passengers were discovered in a probe into the aircraft's door falling apart when it started moving while attached to an aerobridge!
"Of these three, one woman passenger was accommodated in the cockpit and two others on the foldable seats where cabin crew sits during take off and landing," said sources. The DGCA can now take criminal action against AI for this violation. The cockpits in modern aircraft have three seats. While two are for the pilot and co-pilot, the third is called a jump seat which is usually vacant. Since the process of issuing boarding passes is completely computerized, the system stops generating passes once a flight is full. In this case, however, the probe has found that boarding passes were allegedly issued manually to enable the extra passengers to clear the different levels of pre-embarkation security checks.

This action by the airline was a gross violation of the air safety norms. In this case, the airline was caught because of another incident, and this fact came out during the investigation.