Sayantan Misra 10 April 2020
G.L.N. Prasad (Retired employee.) 11 April 2020
File RTI Application and seek a copy of such norms/ laid down rules/orders that considers them as communication channels. However, email is certainly the best communication way that has legal sanctity, if that is followed by duly signed hard copy through registered post. As already suggested in reply No.1, it depends on circumstances, as banks register such a Cell phone number and act electronically.
Dr J C Vashista (Advocate) 13 April 2020
Such calls are admissible in evidence with a certificate u/s 65 B of Indian Evidence Act, 1872, which is applicable through out the territory of India, including WB.