ORDER

Heard the counsel for both the parties.

Leave granted.

2. This appeal is preferred against the judgment of a Division Bench of the Calcutta High Court dismissing the writ appeal preferred by the appellants. The respondent was a Commissioned Officer. He retired on May 18, 1982. According to the Rules then in force, only 2/3rd of the pre-commissioned service was allowed to be counted towards qualifying service for earning pensionary benefits. A minimum period of qualifying service was also provided for becoming eligible for pension. On the basis of the said Rule, the respondent was found ineligible for grant of pension and accordingly no pension was granted to him. About four years later, the Rules relating to qualifying service were changed (with effect from January 1, 1986) based upon the recommendations of the Fourth Pay Commission. One of the features of these Rules was that full pre-commissioned service was to be taken into count for working out the qualifying service required for earning pensionary benefits. In other words, whereas previously only 2/3rd of the pre-commissioned service was to be taken into count for determining the eligibility and the quantum of pension, the