Truth is best defence in defamation case 

you have not maligned her reputation and posted any defamatory allegations against her 

it is necessary to peruse the legal notice sent by wife to advice further 

1. The second question is answered first; filing a complaint in police, filing a suit and complaint in Court, making complaint to appropriate authority is not a defamation. If that is defamation, then all cases filed in Court will become defamation. That is not the purpose of offence of defamation.
2. Under exception (iii) paragraph second of Section 354D, the act described there is not an offence if it is proved that, in the particular circumstances such conduct was reasonable and justified.
3. For any allegation of offence committed in the course of judicial proceedings, it is the presiding officer of the Court who has to initiated criminal proceeding against the offender. She is totally misguided in issuing the notice to your. You can use this answer to reply her. Nothing more than that is required.
4. There is no privacy between husband and wife, Section 354 D is not meant to be used against husband by wife or vis versa.

Dear sir,

Your act cannot be considered as defamation. The snaps were taken only for purpose of evidence and the section of 354-D does not apply here. Even if she files such a case, you can always defend yourself as you had no intention to destroy her reputation and were stating the truth. Thank you.

Defamation case on this ground does not lie. So even if she files you can challenge it in high court under quashing. 

- As per Supreme Court, One is bound to tolerate criticism, dissent and discordance but not expected to tolerate defamatory attack,

- Under sections 499 and 500 of the Indian Penal Code, defamation is a criminal offence. Defamatory acts can include “words either spoken or intended to be read", signs or visible representations, which are published or put up in the public domain. The offence is punishable with up to two years imprisonment, a fine or both.

- If , you have taken snap shots from your wifes phone for producing the same as an evidence , then it will not considered as defamatory act and it not come under the offence till the time there is no divorce. 

To harass you wife may file false defamation case against you 

The referred section states:

Whoever commits the offence of stalking shall be punished on first conviction with imprisonment of either description for a term which may extend to three years, and shall also be liable to fine; and be punished on a second or subsequent conviction, with imprisonment of either description for a term which may extend to five years, and shall also be liable to fine.

Since you have received legal notice it becomes your duty to issue a suitable reply notice denying the commission of said offence. 

The first part of the referred section states that:

(1) Any man who—

1. follows a woman and contacts, or attempts to contact such woman to foster personal interaction repeatedly despite a clear indication of disinterest by such woman; or
2. monitors the use by a woman of the internet, email or any other form of electronic communication,
   commits the offence of stalking;

However it can be challenged in court of law stating that you have not stalked her neither you are a third person. That you have produced the contents found in her mobile phone as evidence before court of law, the court has since accepted this evidence hence it cannot be termed as an offence as falsely accused by her.

The referred section is a criminal offence which is not applicable here and also it may not be an imputation to file a defamation case.

You may proceed with the evidence in all other matrimonial dispute between you both,. 

You can challenge the same if at all he is still proceeding with the proposed case despite you issuing a reply notice. 

Reply to the contents. It is a criminal offence and not defamation. 

G.Rajaganapathy 

High Court of Madras 

Dear Sir,

There is no defamation under those provisions and you may prove your case accordingly.