The phrase "academic justification for" is correct and usable in written English.
It can be used when discussing the rationale or reasoning behind an academic argument, theory, or approach.
Example: "The researcher provided an academic justification for the chosen methodology in the study."
Alternatives: "scholarly rationale for" or "intellectual basis for".
"Three academics are to launch a new open-access platform that they hope will allow researchers to wrest control of peer review from journals and remove academic publishers' justification for charging high prices for their titles.
We argue that the 1915 Declaration of Principles, together with World War I, provides contemporary academics important historical justification for rethinking academic freedom and faculty governance in light of neoliberalism and what we argue is an increased corporatization of higher education in the United States.
Given the perilous academic job market, the traditional justification for refusing the union the idea that graduate students were apprentices, preparing for a lifelong vocation no longer resonated.
They are more than happy to have Stanford academics make a twisted moral justification for them.
The magazine described counter-terrorism as "a sullied sub-academic doctrine" and "a bogus intellectual justification for authoritarianism, military repression and neoconservative Islamophobia".
Picking the most interesting student body is not the only justification for seeking a diverse academic class.
This framing of harms to 'others' as reaching a 'crisis' (Editorial journalist, Independent on Sunday, 24 January 2010) 'we can't afford to do nothing about' (Academic, Sun, 26 September 2011) served as a justification for considering the new policy action.
One piece of research, carried out by London academics Steve Machin and James Vernoit, into the original Labour academies, was heavily used as justification for forced academies in the early days of this government.
And this is proving to be the justification for why we need the government to help guide women's academic choices.
