Forgery/ bogus case of receiving theft item

Sir/Madam Hi my name is pradeep my relative has a jewellery shop he has not studied much and a decent guy, i have seen him suffering from past 4 to 5 years in a forgery bogus case of receiving the theft ornaments by police officers from any station of the city they come with some criminals/culprits to shop and they begin their harassment telling that do you know this guy, he the shop keeper has never seen his face ,its the first time he is seeing that guy they ask that culprit what did you sell him just tell he tells some ornaments i have sold to this guy when the shop keeper tells them that he is lying i have never bought any item from him the make baseless calculation of ornament weighing of high value and frame the shop keeper when the repeated no araises from shop keeper they take the shop keeper along with them to the station in their vehicle there they start keep on harassing the shop keeper by give the ornament or else they will make an arrest ,seize their shop ,take the finger prints of shop keeper and if stil the shop keeper does not agree they start threatening him, the shop keeper even cannot raise his voice if he does they threat him by telling we will make you suffer you will leave this city and frame cases from all other station on you by this all torture the shop keeper agrees for settlement on negotiation and they also agree and the the negotiation starts between them and then the agreed/negotiated quantity of ornament is given to them and the shop keeper is let off to go home, till the settlement is not done they wont leave them to go home 2/3/4 days they will make him sit there till he never come to their negotiations no written document/ copy will be given if they ask they tell you have to come to court roam for the case when ever the summons is issued by hearing the name of court the shop keeper makes a distance, I have seen him suffer many times even i have gone with him in these cases we even told them you can see the cctv cam if we have taken their will be recording they never agree our words the tell you bought it outside the shop, they tell us that what the culprit is telling is the truth there are many shops why did he show us your shop they never agree our words their torture is unbearable my relative is fed up with this harassment from the police department in the recent happened case he was telling me that he will commit suicide by this unbearable torture i am really worried about him he never want to go against police and suffer by some fake cases he never does any illegal things in his shop who ever see those culprits no one will buy a mg from them so sir/madam please help me what is the advise we should follow in certain case what legal action can be taken to proove our self not guilty in such cases.