Wiktionary
conclusively presumed
a. (context legal English) Presumed by law to be true, and therefore providing no opportunity for evidence to the contrary to be presented.
Usage examples of "conclusively presumed".
Whenever it is said that a certain thing is essential to liability, but that it is conclusively presumed from something else, there is always ground for suspicion that the essential clement is to be found in that something else, and not in what is said to be presumed from it.