Introduction
how parties was responsible for marshal law
1. parties was at logger head with each , no consensus on single issue like consititution
2. Parties of Pakistan had no vision regarding constitution, except awami league( having six party agenda)
3. Immature politics (not accepting the mandate of other parties :blamed corruption)
4. No mechanism to gave leaders that lead a country ( parties worked authoritarian )
5. Short sightness in policy making
6. had no long term objective and manifesto
7. violence in politics done by parties
conclustion
this is simple outline , you can elaborate these points