Technically (though this might appear pedantic) the idea that you, the speaker, are the one who must look at the document is not stated unequivocally. It might be that the enquirer needs to see the document, or it may be that there is some other reason why the speaker needs to see the document.
There are more possible interpretations: you might say something like "The answer to your question is in document X, which I must review in order to give you an answer".
However, be careful to say what you mean: "I must look at document X in order to give you an answer" might mean "I need to consult document X in order to know if I am authorized to give you the answer" or "I need to consult document X in order to know if you are authorized to have that information"- two more, quite different meanings.
We have to be careful about idiomatic speech; it is easy to convey unintended messages.