Mother-in-law threatening

As per your situation you should obtain some proofs which can be later on used as evidence to prove that your mother-in-law has been harassing you for a while by threatening to file a false FIR and a false complaint (for jewellery and items that you've already provided in court).

As per the scenario, you may proceed to file a suit under sections 503, 354 and 420 of Indian Penal Code (IPC) for Criminal Intimidation, Harassment and Cheating respectively.

# Section 503 of IPC deals with - Criminal intimidation.

The section further states that -
"Whoever threatens another with any injury to his person, reputation or property, or to the person or reputation of any one in whom that person is interested, with intent to cause alarm to that person, or to cause that person to do any act which he is not legally bound to do, or to omit to do any act which that person is legally entitled to do, as the means of avoiding the execution of such threat, commits criminal intimidation."

# Section 420 of IPC deals with - Cheating and dishonestly inducing delivery of property.

The section further states that -
"Whoever cheats and thereby dishonestly induces the person deceived to deliver any property to any person, or to make, alter or destroy the whole or any part of a valuable security, or anything which is signed or sealed, and which is capable of being converted into a valuable security, shall be punished with imprisonment of either descripttion for a term which may extend to seven years, and shall also be liable to fine."

Filing in a suit as per the above mentioned provisions will help you to get rid out of the situations/problems that your mother-in-law is creating.