Caste reserved employee matters

My father is working with maharashstra sale tax department since last 30 years , on 31/09/2016 he retired from job as per age. while he joined service the oppointment letter has not mentioned any caste base reservation . so while in working in service my father provided vjnt/pardeshi-bhamta caste certificate but while caste verification community given pardeshi -dhangar validity cerificate . so the department raised that he cheated with department for getting job on caste reservation while even they got letter from seva yojan office that my father was opppoinment was on caste resevation or open bases was not to be sure due to the pepers has been missing . provisional pension for 6 month was given to my father but all other retirement benefit is stopped . now they found that my father has cheated with department for getting job .. whilw administration does know the truth of oppinment was on caste resevation or on open catogry upto 2014 year now my father was retired and enquiry officer proved that oppoinment was on cast base . so if depatment has punishment can stop the pension . while we lodged case in mat , mumbai my lawyer given refrence of arun sonone vs state of maharashtra case