Bro, it doesn't work that way. Only the law that contradicts the Holy Qur'an and Sunnah is considered un-Islamic, all other laws are considered Islamic. So, it's the "contradiction" that has to be proven, not the "agreement".
The Constitution of Pakistan states that no law shall be enacted which is repugnant to Injunctions of Islam. Shariat Petition Nos.26/I of 1994, 2/P of 1996 and 2/I of 1996 were filed to challenge the validity of section 6 of the Muslim Family Laws Ordinance, 1961 as opposed to the Injunctions of Islam.
The Federal Shariat Court, after hearing the detailed arguments, ruled:
" ...we would hold that subject to our observations and recommendation in para.92 to amend the provisions of section 6 of the Muslim Family Laws Ordinance, 1961,
the said provision, are not violative of the Injunctions of Islam."
The detailed judgement of FSC where this argument/contention (that the Muslim Family Laws Ordinance, 1961 is violative of Islamic injunctions) is thoroughly discussed and summarily refuted :
https://gmlaw.wordpress.com/2013/10...s-of-muslim-family-laws-ordinance-un-islamic/