How to deal with verdict on encroachment

I am asking this question on behalf of my friend.his father owns an agricultural land.adjoining the land there is way which is like a govt. Property not to be encroached but my friend and his family somehow managed to use that as a part of their own land.lately one of the neighbouring land owner filed a complain to Tehsildar.after two- three hearings verdict was out and tehsildar exercising his powers awarded the maximum punishment of three months' imprisonment under rajasthan land records act.although he is going to appeal against this decision to additional district magistrate in hope of replacing the imprisonment with fine. but before all this he wants to know the procedure for all this.his father was misinformed about the hearing dates and judgement was delivered in his absence like an ex parte.was it ok?can a ex parte judgement be passed?to my mind first order of eviction or notice of eviction with show cause should have been passed and then legal procedures should have started.i want to know what offence is this and what maximum punishment can be awarded in these cases?