In the 1980s, the bicameral parliament, unable to successfully challenge the tradition of bureaucratic dominance over state affairs, was overshadowed by the executive branch. The National Assembly continued to be an instrument of cabinet rule, with its legislative agenda issuing for the most part from the executive branch.
Under the Constitution, the National Assembly was structured to accommodate both the military and civilian bureaucratic elite and the electorate. The influence of the traditionally powerful bureaucracy was channeled through the Senate, whose members were nominated by the prime minister for pro forma appointment by the king. Up to 85 percent of the Senate membership in the late 1980s was drawn from the armed forces and the police. The intent of this arrangement was to encourage the military to play its traditional political role through the upper house rather than through a coup or countercoup.
Senators served a term of six years, and one-third of them were retired every two years. Retirees could be reappointed for an unlimited number of terms. A senator was required to be at least thirty-five years of age, a Thai citizen by birth, and not a member of any political party. Other membership qualifications were broadly phrased, including the requirement that appointees have "knowledge and experience in various branches of learning or affairs which will be useful to the administration of the state."
House of Representatives members represented the populace. They were elected for a four-year term by direct suffrage and secret ballot at the ratio of a member to each 150,000 inhabitants. Each province (changwat), regardless of population, was entitled to at least one seat. A constituency with a population in excess of 75,000 also qualified for a seat. A candidate had to be at least twenty-five years of age, a Thai citizen by birth, and a member of a political party. As a rule, an election had to be held within sixty days from the expiration of the four-year term of the lower house. When the House was dissolved by royal decree (on the recommendation of the prime minister), a new election was required within ninety days.
The two chambers conducted their business separately under their respective presidents (speakers) and vice presidents, who were chosen from among the membership. Under the Constitution, the president of the Senate was automatically the speaker of the National Assembly and in that capacity was empowered to play a strategic role in the selection of the prime minister.
In the 1980s, lower house members demanded that their president, rather than the president of the upper house, have a decisive role in the process of selecting the prime minister. This policy was necessary, they said, because the House of Representatives, not the military-dominated Senate, collectively represented the will of the electorate. A bill to amend the Constitution to make the lower house speaker the president of the National Assembly was introduced in 1986 but failed to pass.
In 1987 the customary role of the Senate as a major vehicle for the power of the bureaucracy and a counterweight to the elective lower house remained little changed, even though its stature seemed to have diminished somewhat after April 1983. At that time, certain senatorial powers granted under temporary clauses of the Constitution expired despite the army’s efforts to have these clauses extended (see Political Developments, 1980-87 , this ch.). Under these clauses, the Senate had had the power to deliberate jointly with the lower chamber on annual appropriation bills, on "an important bill relating to the security of the Kingdom, the Throne, or the national economy," and the power to vote on no-confidence motions. The army and its political allies in parliament failed to have the clauses extended because of factious squabbles. If they had succeeded, the military’s political power would have been enhanced greatly.
The lapse of the transitory provisions, however, did not affect the Senate’s power to address such matters as the appointment of a regent, the royal succession, reconsideration of a bill vetoed by the prime minister, constitutional interpretation, a declaration of war, the ratification of treaties, the appointment of members of the Constitutional Tribunal, and constitutional amendments. In joint sessions senators also could render their opinion on any aspect of affairs of state to the prime minister when requested to do so by the latter. Such opinion was advisory and nonbinding.
Bills could be introduced only by the Council of Ministers or the members of the House of Representatives. Major legislation originated mostly in the cabinet, but only the lower house, with the prior endorsement of the prime minister, could initiate an appropriations bill. An ordinary bill had to be sponsored by a political party and endorsed by at least twenty party members. Bills were passed by a majority, the quorum being not less than one-half of the total members of either house in which the bills originated.
A bill passed by the House was sent to the Senate. The Senate was required to act on an ordinary bill within ninety days and on an appropriations bill within sixty days. If the Senate failed to act in either case, the bill was considered to have been consented to by the Senate, unless the lower chamber had extended the time. Disagreements between the two houses were resolved by a joint committee. When the dispute pertained to an appropriations bill and the lower house voted to reaffirm the bill it had originally passed, the prime minister was required to present the bill to the king for his assent and promulgation. At that point, the prime minister could exercise his important legislative role. He might advise the king to approve or veto the bill; in the latter event, the National Assembly needed two-thirds of its total membership to override the royal objections (actually the prime minister’s objections).
Members of the assembly, who had parliamentary immunity, could question formally a cabinet minister or the prime minister on any appropriate issue except one in which executive privilege was involved. A motion of no-confidence against either an individual minister or the cabinet en masse could be initiated only by members of the lower house. Such a motion required an affirmative vote of at least one-half of the lower house membership. Senators could not take part in no-confidence debates.