In a review of Pakistani court cases by SAHR on inheritance, one particular judgment dealt with brothers ousting out their sister from a share of her inheritance, on an alleged "moral basis".
This judgment is important for two reasons:
Dispossession by brothers against their sisters is a common occurrence in Afghanistan. Brothers are the large majority of disputants against women's inheritance. This can come in the form of a forceful eviction, a threat of non-maintenance/ support in the future, and at times, on the part of the sisters, a "voluntary" waiver of right. Dispossession need not be accompanied by physical force as social pressures are powerful enough to effect an outcome in favour of male heirs. Thus this judgment is particularly relevant to legal actors confronting these situations.
The three petitioners in the case were the sons of Ghulam Ahmed Shah and, the respondent (his daughter and their sister). The father left behind property in different estates at the time of his death. Mutations were entered and sanctioned properly in all estates except for one. She was deprived of her Islamic share in her father’s property covered by this mutation.
The petitioners’ (brothers) explanation for this discriminatory treatment of the respondent’s (sister) share was based on the fact that the petitioners (brothers) had spent a great sum of money on their sister’s marriage. They further claimed that they had maintained her for about five years. The petitioners thus claimed that for these considerations, the respondent (sister) voluntarily relinquished her inheritance.
On the general principle of treatment of women in Islam, the judge referred to a hadith:
“for perfection as a Muslim, it is a necessary qualification that he should be “best among them to his women folk (in treatment). Referring to women as “crystals”, the Prophet (P.B.U.H.)... wanted to give a measure of the best treatment to women. In the present context, these injunctions, enjoin upon men (to protect) women’s rights in every field. Inheritance is not an exception.”
It is noteworthy that the Judge underscored how Islam places upon men a duty to protect women’s rights in each and every field, inheritance not being an exception. The judge in this case declared that:
“it is against the spirit of those rights, to hold that a brother can legally claim “adverse possession” against his sister.”
On the duty of a brother to his sister; brothers cannot intervene into sister's property
“In the Holy Quran and the Sayings of the Holy Prophet (P.B.U.H.), emphasis has been laid again and again on the best possible concern and treatment of female relations.”
Quoting from the Quran (4:34), the Judge reflected on how men are the “protectors and maintainers of women” and how a brother is responsible for the maintenance of his widowed or divorced sister. To respond to the brothers' defence, the judge replied that the brothers had merely discharged their religious duty and they could not claim it as a ground for ousting their sister from her inheritance.
The Judge also stated that when a property is apparently divided without reference to female heirs, this will not be deemed valid. A right cannot be removed through an illegal act.
Quoting another judgment:
“The brother, the father, husband, son…cannot intervene. Here we are dealing with the brothers trying though illegally, as if a guardian-in-inheritance-so-called, on allegedly “moral” basis, to take her inheritance. It is clearly prohibited by Islam. The females cannot be treated so in our system. And we cannot in the present system … apply any (system) in preference of our own.” 
A social custom even if functional and morally justified cannot replace Islamic law. Islamic law has specified fixed shares for women. If these shares could be adjusted by choice by individuals or state authorities, then what authority does the Islamic law carry?
1. Whether the petitioners (brothers) could use a moral reason to take their sister’s inheritance?
The Judge decided that this was alien to Islam. The brothers…had no “moral” ground to oust their sister from their father’s property as the interest in property devolved on the sister automatically after the father’s death. Further, the Court said that it was the brothers’ moral obligation in Islam to maintain their widowed/divorced sister.
The brothers tried to argue that they were an ‘intermediary’ for their sister. But the Judge responded that the concept of ‘intermediary’ is unknown to Islamic law. In Islamic law, there is no intermediary. The property is devolved on the heirs automatically and immediately in definite shares.
“…. whether they (the brothers) like it, want it, abhor it, or shun it…. It is the public policy of Islamic law…If the State, the Court, the executor,[Natasha L1] the administrator (cannot) intervene, (then nobody) intervenes on any other principle, authority or relationship—(not) even of kinship.” 
“It has already been held that the devolution of property through Islamic inheritance takes place immediately without any intervention; therefore, in this case the respondent became the owner of the property immediately on the death of her father.”
2. Whether the sister can relinquish her inheritance in Islamic Law.
The Judge extensively quoted from Quran to establish that a woman under Muslim Law enjoys equal rights and privileges as men and this is true even in case of inheritance. Also, by virtue of Quran (4:34), Islam enjoins upon men the duty to protect and enforce the rights of women.
“Relinquishment” by a female of her inheritance is undoubtedly opposed to “public policy” as understood in the Islamic sense. Accordingly….in agreeing to the relinquishment (though denied by the sister) it was against public policy”
It is against public policy to permit women to easily give up her inheritance. Thus in most cases, it should be declared void.
Therefore, in the Court’s opinion even if the sister had herself waived the right of inheritance, this being against public policy, would invalidate the agreement to relinquish inheritance rights between petitioner and the respondent. The legal recognition of relinquishment should be taken by courts as an exception to the Islamic norm, and not routine. Courts should be directed to avoid arguments that a female relative will eventually be supported by her husband. The argument fails on two counts.
The Judge summarized the power of his arguments through a persuasive reading of the rights of women.
“It is unimaginable that a daughter enjoying “protection and maintenance” by the father till she is married, when she is married and divorced, would lose this right—this of course is subject to certain conditions…it would be her right to be treated by the father in the best possible manner in all these circumstances. And if beyond the bare necessity he does anything concerning the daughter, it has to be treated as gift and not something which would have to be returned by the daughter by compensating the father in the tangible property. The rights of a sister, in cases like the present case, will have to be equated with that of a daughter…”
“…it might be very rare that a male co-heir would relinquish his right for a female heir. Experience shows that is has always been the reverse. The flow of love cannot be so unnatural. Therefore, (…) in cases like the present one there will be a presumption (...) that it was not on account of natural love but on account of social constraints (…) that relinquishment has taken place. (…) In the present case, it appears to be jugglery that the petitioners claimed that the relinquishment by the respondent was in consideration of what they claim to have done in her two marriages as also for her maintenance. (…) All these claims are against the teachings of Islam- injunctions in the Holy Qur’an and the Sayings of the Holy Prophet (PBUH), wherein emphasis has been laid again and again on the best possible concern for and treatment of female relations.”
 Devika Agarwal. “SAHR Case Review: Ghulam Ali (Petitioner/Defendant) v. Mst. Ghulam Sarwar Naqvi PLD 1990 SC 1” (June 2012).
 SAHR's Case Law Program examines case law from Pakistan, India and Bangladesh on women's rights.
 PLD 1990 SC 1, p. 19 and 20 of Judgment
 Ibid., p.11
 Haji Nizam Khan v Additional District Judge, Lyallpur
 P. 12 of Judgment
 P. 17 of Judgment
 P. 21 of Judgment
 P. 23 of Judgment