Just stumbled across this article from 1998 which raises the possibility of Dutch influence in the Declaration of Independence. According to the article, the Dutch Plakkaat van Verlatinge (1581), which was issued in reponse to Spanish rule in Holland, is similar in content to the Declaration. The former lists things such as grievances against the foreign king; attempts to redress; and the right to revolt. I just wanted to point this out, since I know that attempts have been made at determining the source(s) of the Declaration. I imagine that the general concensus would take the safe-scholar route by claiming that in all likelihood, the Declaration is derived from multiple sources (e.g. Locke, the Plakkaat, Aquinas, etc.).
We must be careful when trying to fashion sources for historical documents. This tends to tempt historians to overlay personal themes onto historical events that don’t quite fit. It is highly possible if not probable, that Jefferson read some Dutch materials which inspired him in some way. I, however, find it pointless to “redact” historical documents to somehow delve into the mind of the author. I find it more beneficial to recount the intentions of the document in question rather than become distracted with linking it to other documents. For example, the Declaration of Independence was a document designed to argue constitutionality of British imperial behavior toward the colonies. It’s intent was to declare independence on legal grounds as argued by professional lawyers writing a legal brief to George III and Parliament. Whether or not the colonists used Dutch legal theory etc…in the fashioning of their arguments is a sidenote. Having said this, the Magna Charta should not be overlooked in its influence on the Constitution. Clearly British commonwealth laws and precedents were preserved in modified forms one way or another.
I differ with you at least on one point. The Declaration cannot be reduced to a legal brief in the sense that it was not an appeal to the human law in its content. It did not argue “constitutionality”, but to a kind of universal morality which they claimed supported their actions. It was only because of the grievances that the king had committed that they were morally justified in their separation. But these listings of events related to the human law was not an appeal to that law. With that in mind, the Dutch document that I referred to (which I have not read) would not have been a model of "Dutch legal theory" that Jefferson would have adopted, but rather a philosophically-grounded document that appealed to man's universal rights that Jefferson may have adopted. Clearly, the justification for revolting against one's government needed to be based in a coherent philosophical framework. As the Declaration states, "Prudence, indeed, will dictate that Governments long established should not be changed for light and transient causes...". In substance, the Dutch document could have offered such rational arguments which the American Colonists could have trusted as being echoes of man's universal rights. Taking arguments that were perceived to be morally legitimate from a past revolution with similar circumstances is actually quite plausible and would justify the Colonists in the eyes of God and of world opinion. That said, I agree that scholars must be careful when connecting separate historical events/motives without more evidence than coincidence or tenuous linkage. I think that without such evidence, the question of Dutch influence remains a question, but it is an interesting topic of exploration.