A division bench of Apex Court explained who is eligible to claim maintenance u/s 125 Cr.P.C. and under what conditions.

From Para 7,

7. Under the law the burden is placed in the first place upon the wife to show that the means of her husband are sufficient. In the instant case there is no dispute that the appellant has the requisite means. But there is an inseparable condition which has also to be satisfied that the wife was unable to maintain herself. These two conditions are in addition to the requirement that the husband must have neglected or refused to maintain his wife. It has to be established that the wife was unable to maintain herself. The appellant has placed material to show that the respondent wife was earning some income. That is not sufficient to rule out application of Section 125 CrPC. It has to be established that with the amount she earned the respondent wife was able to maintain herself.

Heart and soul of this judgment from Hon’ble Apex Court is in Para 8.

In an illustrative case where wife was surviving by begging, would not amount to her ability to maintain herself. It can also be not said that the wife has been capable of earning but she was not making an effort to earn. Whether the deserted wife was unable to maintain herself, has to be decided on the basis of the material placed on record. Where the personal income of the wife is insufficient she can claim maintenance under Section 125 Cr.P.C. The test is whether the wife is in a position to maintain herself in the way she was used to in the place of her husband. In Bhagwan v. Kamla Devi (AIR 1975 SC 83) it was observed that the wife should be in a position to maintain standard of living which is neither luxurious nor penurious but what is consistent with status of a family. The expression “unable to maintain herself” does not mean that the wife must be absolutely destitute before she can apply for maintenance under Section 125 Cr.P.C.

Citations: [AIR 2008 SUPREME COURT 530], [2007 AIR SCW 7416], [2008 CRI LJ (NOC) 186], [2008 CRI LJ (NOC) 2], [2008 (1) AIR JHAR R 664], [2008 (1) SRJ 29], [(2008) 1 MH LJ (CRI) 644], [(2008) 1 JCC 486 (SC)], [2008 (1) CALCRILR 416], [2008 (1) SCC(CRI) 356], [2008 (2) CRI RJ 401], [2008 ALL MR(CRI) 860], [2008 (2) SCC 316], [2007 (13) SCALE 402], [2007 (8) SUPREME 525], [(2008) 1 MPHT 13], [(2008) 64 ALLINDCAS 735 (CHH)], [(2008) 1 CGLJ 228], [(2008) 1 CHANDCRIC 27], [(2008) 1 DMC 22], [(2008) 1 CIVILCOURTC 233], [(2008) 2 GUJ LR 1159], [(2008) 1 HINDULR 130], [(2008) 2 JAB LJ 70], [(2008) 1 MADLW(CRI) 615], [(2008) 2 MAD LJ 481], [(2008) 1 MAD LJ(CRI) 1400], [(2008) 2 MARRILJ 605], [(2008) MATLR 775], [(2008) MATLR 165], [(2008) 39 OCR 383], [(2008) 1 PUN LR 263], [(2008) 1 RAJ LW 142], [(2008) 1 RECCRIR 163], [(2007) 4 CURCRIR 408], [(2008) 1 RECCIVR 136], [(2008) 2 ALLCRIR 1409], [(2008) 3 CGLJ 473], [(2008) 1 CAL LJ 166], [(2008) 1 ALLCRILR 342], [(2008) 105 CUT LT 729], [(2007) 3 JCC 2446 (DEL)], [(2008) 1 KER LT 41], [(2008) 1 RAJ CRI C 35], [2008 CRILR(SC&MP) 1], [(2008) 1 CRILR(RAJ) 1], [2008 CRILR(SC MAH GUJ) 1], [2008 (1) ALD(CRL) 97], [2008 (1) ANDHLT(CRI) 131 SC], [2007 INSC 1190]

Other Sources:

https://indiankanoon.org/doc/1720873/

https://www.casemine.com/judgement/in/5609ae55e4b01497114137ad

https://www.the-laws.com/Encyclopedia/browse/Case?caseId=007002893100&title=chaturbhuj-vs-sita-bai

[Landmark Judgement] Chaturbhuj v/s Sita Bai (2008)

Index Maintenance Judgments under Section 125 Cr.P.C. is here.