In this structure, the verb dasi ‘kill’ takes the NP baba ‘father’ as its immediate object. The verb and this object form a complex predicate V' that takes another object, the “outerobject.” The outerobject controls the possessor Pro and is in turn NOP-moved to IP, where it is coindexed with Zhangsan under predication. (Both predication and control are subject to a Minimal Distance Principle of the sort first proposed by Rosenbaum (1970), as part of the Generalized Control Theory of Huang (1984a, 1992), inter alia.) We take the standard view that theta-role assignment is compositional. The inner object receives the Patient/Theme role from the verb dasi, and the outer object receives the Affectee role from the V' dasi-le Pro baba.
I looked at Rosenbaum's paper, but I didn't find any kind of precise statement. So with a reference to this analysis for example (the tree is given below), what is Minimal Distance Principle, and how is it applied?