Step 1: Understanding the Concept:
The question asks for the legal issue decided in the famous case of Rupa Bajaj v. K.P.S. Gill. The full name is Mrs. Rupan Deol Bajaj & Anr vs Kanwar Pal Singh Gill & Anr.
Step 2: Detailed Explanation:
This case involved an incident where a senior police officer, Mr. K.P.S. Gill, allegedly patted the posterior of a senior IAS officer, Mrs. Rupan Deol Bajaj, at a party. A criminal complaint was filed against him.
The legal question revolved around whether this act amounted to an "outrage of the modesty of a woman," which is an offense under Section 354 of the Indian Penal Code ("Assault or criminal force to woman with intent to outrage her modesty").
The Supreme Court, in its judgment, held that the act did constitute an offense under Section 354 of the IPC. The court provided a detailed interpretation of what constitutes 'modesty' of a woman and what kind of act would amount to outraging it. The conviction of Mr. Gill was upheld.
Step 3: Final Answer:
The case of Rupa Bajaj v. K.P.S. Gill was decided on the issue of outraging the modesty of a woman.