If a person prepares backdated letters in word processor and takes a print out of it signs the letters and submit them to the police. Later files a false case in different PS. He/She contradits his/her statement and denies during cross about those backdated letters submitted in other PS. After recording his/her statement on oath can I use that statement certifiled copies and file a case againt him/her immediately? or should I wait till trial completion. What all are the appropriate sections for this 420 or 463 IPC or any other section?