Can we first claim and then find the evidence when we write the literature review (i.e., using confirmatory technique)? I have a question regarding a researcher’s practice in writing.

Let me give you some background about this issue. Here’s what this researcher does when writing introductions and literature reviews. He makes certain speculations first and then proceeds to making claims based on those initial speculations. It is worth noting that the claims he makes are sometimes too specific. Following that, he starts looking for evidence to support his claims.

I have tried many times to convince him and have told him that this is not the right way to write a research paper. It’s more like writing a composition rather than an academic piece of writing which aims at making contributions to the world of education.

Here’s part of what he recently wrote in an email in response to me:

“I disagree that making claims and looking for evidence supporting them is "not academic". Maybe I am wrong but this approach is less exploratory than the method you have in mind. For example, [Michael] Kane's framework is based on this method: Claim --> evidence. Kane specifically stresses the importance of opinions/judgments etc. I personally do not prefer to tie my mind merely to the literature --I do not find it much academic in the sense it does not engage me in critical thinking. My method is: "The theory I wish to develop does not exist out there; I develop and support it"”

I would like to have your opinion regarding this issue. Is what the researcher claims really right? If not, can you introduce some published sources which have attacked this practice?
Claim -> evidence is a perfectly valid approach. It is just that evidence is not the same as only looking for supporting information, it means critically scrutinizing all aspects that speaks for or against the claim and then drawing an educated conclusion on whether the claim is good or not. In the end the "evidence" is the net outcome of positive and negative support to the claim. So to me the claim that one should come up for an idea an then look for support is either poorly phrased, leading to misunderstanding, or plainly bad.