the National Assembly. Therefore, it is not desirable for other state institutions to intervene and judge the legitimacy of a decision reached by the National Assembly upon matters that fall within the scope of its self-regulating authority, and no exception thereto applies to the Constitutional Court (See 10-2 KCCR 74, 83, 98Hun-Ra3, July 14, 1998). Also, the Speaker of the National Assembly is, in principle, vested with the general and inclusive authority and responsibility concerning the deliberation process of the National Assembly, pursuant to Article 10 of the National Assembly Act. Therefore, in cases of disputes as to the deliberation process at the general meeting or where the normal deliberative process otherwise cannot apply, the method of deliberation and of resolution is to be determined by the Speaker of the National Assembly within the above authority endowed to the Speaker. Such authority of the Speaker to preside over the deliberation process is, widely interpreted, part of the self-regulating authority of the National Assembly, and should be respected as such unless exercised in a way clearly beyond its limit. As a principle, such authority may not be impeded upon by the Constitutional Court (See 12-1 KCCR 115, 128, 99Hun-Ra1, February 24, 2000). B. On the argument that the proceedings at the National Assembly lacked sufficient investigation and deliberation The respondent argues that in order for the National Assembly to petition for the impeachment of the President, the National Assembly must sufficiently investigate the grounds for impeachment and the evidence thereto, to the extent that the Constitutional Court in its impeachment adjudication can readily determine the validity of the alleged grounds for impeachment. It is desirable, as a matter of course, that the National Assembly thoroughly investigate the stated grounds for impeachment prior to its reaching a resolution to impeach. However, Article 130(1) of the National Assembly Act provides that, "upon proposal for the impeachment resolution, ... the National Assembly may, by resolution at the plenary session, assign the matter to the Legislation and Judiciary Committee for investigation," thus subjects the investigation to the discretion of the National Assembly. Therefore, even if the National Assembly did not perform a separate investigation in the instant case, this was not in violation of the Constitution or statutes. - 161 -