citizenship amendment act

my friends kishor mehta...
article 20 says that

(1) No person shall be convicted of any offence except for violation of a law in force at the time of the commission of the Act charged as an offence, nor be subjected to a penalty greater than that which might have been inflicted under the law in force at the time of the commission of the offence.
(2) No person shall be prosecuted and punished for the same offence more than once.
(3) No person accused of any offence shall be compelled to be a witness against himself...
if any foreigner accused say that the term "person" means citizen and I am not a citizen of India so I should not be persecuted in any court of India for any crime then will it be right?
if person means citizen of India then why Articles 15, 16,18 and 19 mention the term citizen? it should have mentioned just "person".
article 18 mentions both terms citizen(s) and person. in clause 4 it includes both citizens and non-citizens. clause 3 talks only about non-citizens and clause 2 talks only about citizens.

With respect to all, the matter is before the Hon. Supreme Court it will be prudent to wait for its decision instead of taxing our brains and arguing unnecessarily.

Raksha Joshi please read article 13 (3)(b)
b) “laws in force” includes laws passed or made by a Legislature or other competent authority in the territory of India before the commencement of this Constitution and not previously repealed, notwithstanding that any such law or any part thereof may not be then in operation either at all or in particular areas.
if the law mentioned above(passes by a legislature or other competent authority in the territory of India) violates fundamental rights or One of the fundamental rights is void ...
whether it is applicable on citizens or non-citizens or the people out of the country, it will be void if it is passed by any competent authority in the territory of India.... parliament of India situated in the territory of India. if parliament passes any act in respect of refugee then article 14 is also applicable to them because article 13 is applicable on every competent authority in the territory of India and the articles 14 and 13 have the same extent of jurisdiction.