That was a strange thing for the Judge to ask. How is the caste of a person relevant to the case ? Makes you wonder if it was a sly way of asking his religion.
Though I am not sure Islam allows for a person to be both a Hindu and a muslim at the same time
1. Shah rukh khans wife is a Hindu, gGauri
2. Saif Ali Khan's wife is a Hindu, Kareena
3. Salim Khans first wife was a Hindu, second wife a christian,
4. Amir Khan wife is a hindu, first wife was a hindu too, Kiran
5. Imran Khan wife is a Hindu, Avantika
6. Abraz Khan wife is a Hindu, Malika.
7. Sohail Khan wife is a Hindu, Seema Sachdev
8. Frhan Akhtar wife is a Hindu, Adhuna Bhabani
So the question is why don't they want to marry a muslim girl ?