I have explained it already in detail why constitution and laws of pakistan need some overhauling.
It is not fault of corrupt people if they loot people because people want to remain ignorant and stupid. If people educate themselves then they can react appropriately to situations.
When people want everything for free without doing the needed work and making needed sacrifices then the corrupt take over a society and do what they like with it. They make the constitution and they make its laws as it suits them.
Understand one thing very clearly, people cannot make right decisions if the system is based upon corruption. So if people want better life as a community they need to work as one people and support each other fully and see all corrupt run for their lives.
To start with, campaign for changes in the constitution in such a way that the constitution becomes logically consistent. Do not stop this campaign till the constitution is completely overhauled. Once the constitution is overhauled properly then it should work fine. I have explained how it can be done in great detail in my work on the quran.
As for case of justice eesa, there is no point is losing heart over it. Because the positive side is, it will definitely expose to sensible people of pakistan what is wrong with the constitution of pakistan. So it is up to people to force their government to fix things in the favour of proper justice. This also means people need to stand with the government so that government could change things the way they should be.
At least this government of imran khan is doing whatever it can to expose the system. It cannot change the system without help and full support of people of pakistan. Moreover things do take time, particularly if public at large is not literate or educated as much as it should be. No one is supposed to be above the law, not a person or any institution and its people. For so long as people ignore this approach nothing much can change in paksitan. For a detailed explanation of things about the quran, deen of islam and pakistan see
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HERE.