Leicester encouraged the extreme Calvinist and democratic faction in the Republic's politics against the Regenten, of which Vranck was a leader.
Such an attack on their legitimacy could not be left unchallenged by the States, who commissioned Vranck to write a blistering reply, which he did in the form of his Deduction (with the very long name[3]).
[4]: xxvii–xxviii This pamphlet took the form of a historical dissertation, going back 800 years to the mythical origins of the county of Holland and its political institutions, and "proving" that since time immemorial sovereignty had resided in the vroedschappen and nobility, and that it was administered by (not transferred to) the States, next to the Count of Holland (whose place had recently been declared vacant by the Act of Abjuration).
It formed the basis of constitutional expositions by Hugo Grotius (Liber de antiquitate reipublicae Batavicae; On the Antiquity of the Batavian Republic, 1610)[7]: 21ff., 89 and Simon van Slingelandt.
The States were so enamored of Vranck that they offered him the post of deputy-Land's Advocate, under Van Oldenbarnevelt, but he had to decline, because the city of Gouda refused to let him go.
He was no Contra-Remonstrant himself, though, as witnessed by his tolerant stance in religious matters expressed in the polemical Wederlegghinge (Refutation) that he wrote against a pamphlet by Franciscus Haraeus' Onpartijdighe verclaringhe der oorsaken des Nederlantsche oorlogs (1612) (Impartial explanation of the causes of the war in the Netherlands), in itself a reaction to the work of Grotius (which in turn was based on Vranck's own work).