The reason Shar'iah law is being attempted in various countries is that it allows the community to wholly ignore secular law.
In the vast majority of Arab states, Shar'iah law and legal institutions work in parallel with the government. By that, Imams and other Clerics can pass down judgments in divorce, civil issues, even cases in settling murders and honor killings. If a government judge hands down a decree, the loser can simply turn to a cleric and try it again. In what usually happens, the loser donates a generous sum to the mosque and amazingly wins the second go-round.
Now I'm willing to accept that in some developing countries Shar'iah is a good thing. Mostly in Northern Africa, the governments are so utterly corrupt civil suits often turn into the local governor grabbing up both defendant and plaintiff's property.... just because. In those instances the Clerics are the impartial parties which the judges are supposed to be, but with that said Shar'iah is NOT something we want. Shar'iah law is what allows the fathers in honor-killings to avoid punishment as the local police do not want to go against a clerical decree.
Shar'iah is not a system to develop law which is the area which you posted. Shari'iah is the legal system of settling disputes through interpretation of laws supposedly handed down by God. In essence your quote is Congress while Shari'iah is the Supreme Court.