(1) The competence of a person to testify, and the number of witnesses required in any case shall be determined in accordance with the injunctions of Islam as laid down in the Holy Quran and Sunnah.

(2) Unless otherwise provided in any law relating to the enforcement of Hudood or any other special law,

(a) in matters pertaining to financial or future obligations, if reduced to writing, the instrument shall be attested by two men, or one man and two women, so that one may remind the other, if necessary, and evidence shall be led accordingly; and

(b) in all other matters, the Court may accept, or act on, the testimony of one man or one woman or such other evidence as the circumstances of the case may warrant.

https://equalitynow.org/discriminatory_law/pakistan_the_qanun_e_shahadat_order_1984_law_of_evidence/