This answer applies mainly to formal English, not to informal English.
Given the fact that the court’s decree is binding and peremptory (paragraph 1 of article 94 of the charter and articles 59 and 60 of the court’s constitution) and the fact that temporary agreement of the court according the court’s view in the June 27, 2001 regarding the LaGrand case was considered binding and the advisory vote of the original court has no requirement for the requesting component and countries, it should be considered what guarantees do exist for implementing any of the above decisions.
The above is your example minus the question mark. The beginning of the sentence does not matter. What matters is the main clause, which is it should be considered... Since that clause is not interrogative itself, the sentence as a whole is not interrogative, which means that there should be no question mark there in formal English. The what clause is a dependent clause, an indirect question, which should not affect the status of the main clause as a non-interrogative clause. The status of the whole sentence is determined by its main clause(s).
Indirect questions normally do not have the properties of direct questions: they do not have inversion, so they do not have the extra do that direct questions sometimes require. As you can see, the subject what guarantees and the verb do are not inverted in your example, so there is no sign of inversion. The do in this case is or should be merely the emphatic do, which is unrelated to the do that is sometimes required after inversion. It is or should be the same kind of do as in this example:
– Your legions do not belong in Italy, Caesar. Their presence beyond the Rubico is expressly forbidden by law.
– My legions do belong in Italy, for who else will protect Rome from the tyranny of the Optimates? Go tell that to Pompey.
If, however, the main clause in your example had been a question, which is not the case, then the sentence should have ended with a question mark, regardless of its beginning. In the below example, I have taken out the old main clause and promoted the indirect question to a direct question, a main clause:
Given the fact that the court’s decree is binding and peremptory (paragraph 1 of article 94 of the charter and articles 59 and 60 of the court’s constitution) and the fact that temporary agreement of the court according the court’s view in the June 27, 2001 regarding the LaGrand case was considered binding and the advisory vote of the original court has no requirement for the requesting component and countries, what guarantees exist for implementing any of the above decisions?
