Question: What position was held between 2013 and 2015 by a man placed under investigation by ruling political party of the People's Republic of China on June 26, 2015?

Context paragraphs:
Communist Party of Ukraine (Soviet Union): The Communist Party of Ukraine (Ukrainian: Комуністична Партія України "Komunistychna Partiya Ukrayiny", КПУ, "KPU"; Russian: Коммунистическая партия Украины ), was the founding and ruling political party of the Ukrainian Soviet Socialist Republic operated as the Ukrainian branch of the Communist Party of the Soviet Union (CPSU).  The CPU was the sole governing party was founded in 1918 as the "Communist Party (Bolshevik) of Ukraine" until 1952, when it became the "Communist Party of Ukraine".  The party was abolished in 26 August 1991 after the failed Soviet coup.

Communist Party of China: The Communist Party of China (CPC) is the founding and ruling political party of the People's Republic of China .  The Communist Party of China is the sole governing party of China; although it coexists alongside eight other legal parties that make up the United Front, these parties hold no real power or independence from the CPC.  It was founded in 1921, chiefly by Chen Duxiu and Li Dazhao.  the communist party grew quickly, and by 1949 the CPC had driven the nationalist Kuomintang (KMT) government from mainland China after the Chinese Civil War, thus leading to the establishment of the People's Republic of China.  It also controls the world's largest armed force, the People's Liberation Army.

People's Democratic Party of Tajikistan: The People's Democratic Party of Tajikistan, PDPT (Tajik: Ҳизби халқии демократии Тоҷикистон / Hizbi xalqii demokratii Tojikiston ; Persian: حزب خلق دموکرات تاجیکستان‎ ‎ ; Russian: Народная демократическая партия Таджикистана ) is a political party in Tajikistan.  Is an officially registered center-left ruling political party in Tajikistan.  It is the largest political party in the country, the so-called «party of power».  Members of the PDPT occupy 51 seats out of 63 in the Majlisi Oli of the Republic of Tajikistan — the parliament of Tajikistan.

Communist Party of Azerbaijan: The Azerbaijan Communist Party (Azerbaijani: "Azərbaycan Kommunist Partiyası" ; Russian: Коммунистическая партия Азербайджана ) was the ruling political party in the Azerbaijan SSR, making it effectively a branch of the Communist Party of the Soviet Union.  It was formed on February 20, 1920, when the "Hummat Party", the "Adalat Party", the "Ahrar Party of Iran" and Baku Bolsheviks joined together to establish the Azerbaijan Communist Party.  On April 1 of the same year, the Fifth Cabinet of Ministers of the Azerbaijan Democratic Republic gave its resignations and all the power to the Azerbaijan Communist Party.  The party ruled the Azerbaijan SSR until 16 September 1991 when it was formally disbanded.  Nevertheless, former leaders and members of the communists continued to play a role in the family- and patronage-based political system.  The Azerbaijan Communist Party won the first multi-party elections in Azerbaijan that took place on 30 September and 14 October 1990 for the Supreme Soviet obtaining 280 out of 360 seats.

Congolese Party of Labour: The Congolese Party of Labour (French: "Parti congolais du travail" ; PCT), founded in 1969 by Marien Ngouabi, is the ruling political party of the Republic of the Congo.  It was originally a Marxist-Leninist pro-Soviet party, which founded the People's Republic of the Congo, but moved towards a moderate left-wing stance in the early 1990s.  Denis Sassou Nguesso is President of the PCT Central Committee, and Pierre Ngolo is the PCT's Secretary-General.

Rally of the Togolese People: The Rally of the Togolese People (French: "Rassemblement du Peuple Togolais" , RPT) was the ruling political party in Togo from 1969 to 2012.  It was founded by President Gnassingbé Eyadéma and headed by his son, President Faure Gnassingbé, after the former's death in 2005.  Faure Gnassingbé replaced the RPT with a new ruling party, the Union for the Republic (UNIR), in April 2012, dissolving the RPT.

Jubilee Party of Kenya: The Jubilee Party of Kenya is the ruling political party that was formed after the merger of 11 political parties, to become one of the major political parties in Kenya.  The ceremony announcing the merge was held at the Safaricom Kasarani Stadium on 8th September 2016.  The formation of the party was the result of an alliance by the principal members of the Jubilee Alliance party, as well as 10 other political parties.  These parties were:

Delta State People's Democratic Party: The Delta State People's Democratic Party (also known as Delta PDP) is the state level chapter of the People's Democratic Party in Delta State, Nigeria.  It is the current ruling political party in the southern oil-rich state and has produced governors since the advent of the fourth republic in 1999.

Workers' Party of Korea: The Workers' Party of Korea (WPK) is the founding and ruling political party of the Democratic People's Republic of Korea (North Korea), and the largest party represented in the Supreme People's Assembly.  The WPK is the sole governing party of North Korea, although it coexists "de jure" with two other legal parties making up the Democratic Front for the Reunification of the Fatherland.  It was founded in 1949 with the merger of the Workers' Party of North Korea and the Workers' Party of South Korea.  The WPK also controls the world's 5th largest armed force – Korean People's Army.  This political party (and all of the other parties in the DPRK) remains illegal in South Korea (officially the Republic of Korea) under South Korea's own National Security Act and is sanctioned by Australia, the European Union, the United Nations and the United States.

Le Dake: Le Dake (; born March 1960) is a former Chinese politician.  He served for state security system in 18 years and, between 2013 and 2015, held the post of the Vice-Chairman of the Tibet People's Congress.  On June 26, 2015, Le was placed under investigation by the Communist Party of China's anti-graft agency.  He was the first high-ranking implicated official being examined from Tibet Autonomous Region after the 18th Party Congress in 2012.

Supporting paragraphs: Le Dake Communist Party of China
Answer: Vice-Chairman of the Tibet People's Congress