Partyforumseasia: Changing the electoral boundaries (gerrymandering)  is the most common and most unnoticed manipulation of election systems, whereas the impact of tweaks and changes in the electoral system may be the most controversially discussed in political science. But even when the outcome for a certain party is difficult to predict, the committees changing the system have effects and outcomes on their minds.

The Bangkok Pundit, Jan 16, 2015 (Link) gives an interesting introduction of what is in the pipeline:
“The CDC (=Constitutional Drafting Committee) is proposing a Mixed-Member Proportional (MMP) electoral system, modeled after the system in Germany. Like Thailand’s previous Mixed-Member Majoritarian (MMM) electoral system MMP gives voters two votes: one for a constituency MP in a single seat electoral constituency, and one for a party list. However, rather than simply adding the party list seats to a party’s constituency seat total, as is done under MMM, the party list vote is used to determine the total number of seats a party receives. The goal of MMP is to make the number of seats each party obtains as proportional as possible to the percentage of party list votes the party receives.”

“The total number of seats in the House of Representatives will be a minimum of 450 and a maximum of 480 seats, at least 20 fewer seats than the previous parliament. The number of constituency seats has been dramatically reduced, from 375 in the 2011 elections to a proposed 250, with about 250,000 people per MP. The number of seats set aside for the party list increases from 125 to 200. At 44 percent of total seats this represents the largest percentage of seats set-aside for the party list since Thailand adopted a two-tier system 2001. Finally, as in 2007 the party list seats are to be divided across 8 electoral regions.”

Testing the difference between MMM and MMP on the 2007 and 2011 elections, the analysis shows that the new system will be an advantage for the Democrat Party. The impeachment process against former PM Yingluck Shinawatra and her forseeible banning from the political scene show anyway the general intention of the changes: Keeping the Shinawatras and the Puea Thai party out.