Domestic enquiry vs leave without pay - Can a private company keep an employee on leave without pay for more than a year?

Guidance required, One of my knowns is going through domestic enquiry where the companies focus is on moral and ethical misconduct. He got discharged from a criminal case but the company has kept him on leave without pay in place of suspension for the last 1 n a half year and still delaying the closure report without giving proper reasons.
Guidance required for points mentioned below:-
1. Can a private company keep an employee on leave without pay for more than a year.
2. Any timeliness for completion of Domestic inquiry (private company)
3. Is there any way to ask for substance allowance for the survival of his family.
Regards

The description of the matter is definitely showing malice and victimisation. Since the criminal case has ended in discharge, is the departmental proceeding on the same set of evidence, then it needs to be examined as to whether it is double jeopardy (means repeated prosecution on the same facts). To keep an employee on forced leave without payment of salary pending disciplinary action is illegal and improper. Is the organisation rule providing for it? If so, it will not stand judicial scrutiny. Is there a rule providing for moral and ethical misconduct? The whole thing looks very vague and illegal, you may consult a good legal expert and take his opinion.

Dear Sir,
I want to know. according to new law to eligible for leave in the year. PL, CL and Sick leave.