Di Indonesia, dalam suasana yang demokratis, pemerintahan koalisi ditemui dalam semua sistem pemerintahan yang pernah berlaku. Realitas koalisi di Indonesia menunjukkan berbagai masalah baik dalam pembentukkannya maupun pengelolaannya, masalah yang dihadapi telah mengancam bahkan merusak stabilitas pemerintahan. Dalam pemerintahan yang dibentuk berdasar koalisi, potensi instabilitas memang lebih tinggi. Praktik penerapan koalisi di negara-negara bersistem parlementer di Eropa Barat menunjukkan bahwa stabilitas pemerintahan dijaga melalui aturan-aturan hukum yang memagari setiap tahapan pemerintahan. Proses politik yang terjadi dalam pembentukan dan mekanisme berlangsungnya koalisi sangat terpengaruh kepada aturan yang berlaku. Negara-negara bersistem presidensial di Amerika Latin juga menghadapi masalah ancaman stabilitas pemerintahan akibat dari dinamika koalisi yang tinggi. Di sistem presidensial Amerika Latin, aturan hukum menjadi alat untuk mendesain suasana yang kondusif bagi pembentukan dan pengelolaan koalisi dalam rangka menjaga stabilitas pemerintahan. Praktik pemerintahan koalisi sepanjang sejarah ketatanegaraan Indonesia dan Praktik pengaturan terkait koalisi di negara-negara parlementer Eropa Barat serta negara-negara presidensial di Amerika Latin digunakan oleh penelitian normatif ini sebagai bahan pendekatan sejarah (historical approach) dan pendekatan perbandingan (comparative approach). Kedua pendekatan ini digunakan untuk mendapatkan jawaban bagi stabilitas pemerintahan dalam pembentukan dan pengelolaan pemerintahan koalisi di sistem presidensial Indonesia berdasar UUD NRI Tahun 1945. Desain aturan hukum untuk menjaga stabilitas pemerintahan koalisi yang terbentuk di Indonesia memperhitungkan realitas sistem kepartaian dan pemerintahan di Indonesia, karakter sistem presidensial dan perkembangan sistem parlementer dalam menjaga stabilitas sebagai tempat berasalnya konsep pemerintahan koalisi. Desain untuk stabilitas tersebut antara lain didapat dari penggabungan pemilihan umum serentak dengan sistem pemilihan presiden plurality atau majority with reduced threshold, pelembagaan koalisi pemerintahan yang sejajar dengan koalisi legislatif, dan penggunaan kekuasaan konstitusional presiden di bidang legislatif sebagai instrumen untuk membangun dan mengelola koalisi pemerintahan.

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In Indonesia, in a democratic atmosphere, the coalition government is found in every government systems ever applied. In the era of parliamentary government, a coalition government is inevitable due to the fact that the parliament was fragmented so that no single party held an absolute majority of the seats. In the era of presidential government, a coalition government is also an option for the elected president even tough coalition was not the source of legitimacy for the ruling government. President who ruled in a highly fragmented multiparty situation chose to form a coalition to ensure the stability of the government. In reality, coalition in Indonesia showed various problems both in terms of the establishment and management. Problems encountered have threatened and even destabilized the government. In a government established under coalition, government stability is is likely to have more problems. Coalition practiced in countries applying parliamentary system in Western Europe show that government stability is maintained through legal rules that hedged every stage of governance. Political processes that occur in the establishment and the mechanism of coalition course are greatly affected by the prevailing rules. Latin American countries applying presidential system also face threats in the government stability due to the high dynamics of the coalition, just like the case in Western Europe. It can be seen on their experience designing a coalition through prevailing rules and laws. Coalition practiced by the government throughout the history of Indonesia and ruling practices in relations to coalitions in Western European countries applying the parliamentary system and Latin American countries applying the presidential system are used by these normative research as a source of historical approach and comparative approach. Both of these approaches are used to get an answer to the stability of the government in establishing and managing a coalition government in Indonesia’s presidential system based on Indonesia’s 1945 Constitution. Legal rulings designed to maintain the stability of the coalition government, take the reality of the party system and the Indonesian government, the characteristics of the presidential system and the development of parliamentary system into account in maintaining stability as the source of the concept of a coalition government. Designs to create the stability are among others received by combining simultaneous election with plurality presidential election or majority presidential election with reduced threshold, government coalition institutionalization parallel to legislative coalition, employment president’s legislative constitutional power as an instrument to form and manage the government coalition.