General Manager, Southern Railway v. A Rangachari (1962 AIR 36)
A circular giving reservation in favour of Scheduled Castes / Scheduled Tribes in promotions (by selection) was questioned.
The Supreme Court held that:
1. The promotion to a selection post is also included in the matters relating to employment.
2. Art.16(1) guarantees equality of opportunity to all citizens who enter service even in regard to promotion.
State of Punjab v. Hiralal (AIR 1971 SC 1777)
The Supreme Court upheld the validity of the Government order providing for reservation in promotion (in addition to initial recruitment) following Rangachari Case.
N M Thomas v State of Kerala ( AIR 1976 SC 490)
The rule giving preference to an unrepresented or under-represented backward community does not contravene Art.14, 16(1) or 16(2), held the Supreme Court.
Indira Sawhney v Union of India( AIR 1993 SC 477)
Whether the Art 16(4) provide for reservation only in the matter of initial appointments / direct recruitment or does it contemplate and provide for reservations being in matter of promotion as well?
The Supreme Court overruling the above decisions and held that reservation would apply at the stage of initial entry only and would not apply at the stage of promotion.
Constitutional (77th Amendment) Act, 1995
The Parliament inserted Article 16(4)(A) thereby enabling the state to pass laws for reservation in promotion for SCs and STs.
Now the position was clear that SC/ST can be given reservation in promotion.
Now the problem of catch up rule and consequential seniority arose.
‘Catch up’ rule means that if a senior candidate of general category is promoted after SC/ST candidates, he would regain his seniority in promotion over the juniors promoted ahead of him under the reserved vacancies while in case of consequential seniority, a senior candidate of general category who is promoted after SC/ST candidates, would not regain his seniority in promotion over the juniors promoted ahead of him under the reserved vacancies
Union of India v. Viral Singh Chauhan (1995 SCC (6) 684)
The Court held that Catch up will apply in matter of promotion.
Ajit Singh And Ors vs State Of Punjab (Appeal (civil) 3792 of 1989)
The Court affirmed Viral Singh Chauhan Case.
Jagdesh Lal v State of Haryana
The Court formulated the rule of consequential seniority and held that seniority will be governed by date of promotion and not initial appointment.
Ajit Singh (II) v. State of Punjab (1999)
The Court overruled Jagdesh Lal Case and affirmed catch up rule.
Constitutional (85th Amendment) Act, 2001
Parliament enacted the Constitutional (85th Amendment) Act which provided consequent seniority for the beneficiaries of reservation in promotion.

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