Prospective tax amendment cannot apply to an earlier assessment year where no retrospective effect is provided.

The Income-tax (Fourth Amendment) Rules, 1983 were held to operate only prospectively from 2 April 1983 and not to affect an earlier assessment year. Because the relevant year was 1981-82 and the amendment was not given retrospective effect, depreciation under the amended rules could not be applied to that prior year. The operative principle is that an amendment expressed to be prospective, and silent on retrospectivity, cannot govern an assessment period that ended before its commencement.

---

---

Issues: Whether the depreciation under the Income-tax (Fourth Amendment) Rules, 1983 applied to assessment years prior to the date the amendment came into force.

Analysis: The amendment rules came into force on 2 April 1983. The relevant assessment year was 1981-82, which was before the commencement of the amendment. Since no retrospective effect was given to the amendment rules, they could not govern an assessment year that had already fallen before their commencement.

Conclusion: The amendment rules had no application to the assessment year 1981-82.

Final Conclusion: Depreciation under the 1983 amendment could be allowed only for periods covered by its commencement and could not be extended to an earlier assessment year.

Ratio Decidendi: An amendment that is expressly prospective and contains no retrospective operation cannot apply to an assessment year preceding its commencement.

---