Who has the authority (Wilayah) to contract marriage for a woman?

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The authority to contract marriage belongs exclusively to the 'Asabah (agnatic male relatives). Relatives such as the uterine brother, maternal uncle, maternal uncle's father, or maternal grandfather do not possess this authority. This position is held by Ahmad in several instances, by Al-Shafi'i, and by one narration from Abu Hanifa. The evidence supporting this is the narration from Ali, who stated, 'When women reach half of their share, the 'Asabah is preferred,' as recorded by Abu Ubayd in Al-Ghareeb. Furthermore, those who are not 'Asabah are treated as strangers in this matter. The authority of the freedman (Mawla) to marry off his freedwoman is established because he is her 'Asabah in inheritance and blood-money (Diyyah) when direct blood relatives are absent. The blood relatives are prioritized over the Mawla in marriage just as they are in inheritance and Diyyah.