What is the effect of improper questioning in a criminal investigation?

87. These proceedings have not reached the stage, in the words of Lord Wilberforce in Wiseman v. Borneman, [1971] A.C. 297, at p. 317, that "it is necessary to look at the procedure in its setting and ask the question whether it operates unfairly to the taxpayer to a point where the courts must supply the legislative omission". Courts must, in the exercise of this discretion, remain alert to the danger of unduly burdening and complicating the law enforcement investigative process. Where that process is in embryonic form engaged in the gathering of the raw material for further consideration, the inclination of the courts is away from intervention. Where, on the other hand, the investigation is conducted by a body seized of powers to determine, in a final sense or in the sense that detrimental impact may be suffered by the individual, the courts are more inclined to intervene. In the present case it was sufficient that the Hearing Officer allowed all the parties to be represented by counsel who could object to improper questioning and re‑examine their clients to clarify the testimony given and to ensure that the full story was communicated by the witness counsel represented.