The following is a chronology of major events leading to the Supreme Court's Thursday ruling of former President Park Geun-hye and Samsung heir Lee Jae-yong.
Oct. 24: Cable channel JTBC unveils Park's confidante Choi Soon-sil's tablet PC indicating her meddling in state affairs.
Oct. 27: The prosecution forms a special investigation team.
Oct. 29: Citizens launch an anti-Park weekend rally. Park's aides reject prosecutors' search of the presidential office
Oct. 30: Choi is detained after returning home after weeks of apparently hiding in Europe.
Nov. 3: Choi is formally arrested.
Nov. 8: Prosecutors raid offices of Samsung Electronics Co. on suspicions of offering bribes to Choi and, in effect, to the president.
Nov. 20: Choi is indicted. Prosecutors name Park as a criminal suspect
Nov. 30: Prosecutor-turned-lawyer Park Young-soo is appointed the special counsel for the case.
Dec. 6: The National Assembly hearing begins on the corruption scandal.
Dec. 9: The National Assembly votes to impeach Park.
Dec. 21: The independent counsel launches its formal investigation.
Jan. 3: The Constitutional Court holds its first hearing in the impeachment trial.
Feb. 17: Samsung's de facto leader Lee Jae-yong is arrested on bribery and embezzlement charges.
Feb. 28: The independent counsel team indicts 17 more suspects, including Samsung's Lee Jae-yong.
March 10: The Constitutional Court upholds the parliamentary impeachment of Park with a unanimous decision, immediately removing her from office.
March 21: Park is questioned by state prosecutors over the scandal for the first time.
March 31: A court issues a warrant for the arrest of Park. She is placed in custody at a detention center just south of Seoul.
April 17: Prosecutors indict Park on multiple charges, including bribery and abuse of power. Lotte Chairman Shin Dong-bin is also put on trial.
May 9: Moon Jae-in wins the election to become South Korea's 19th president.
May 23: A court begins the criminal trial of Park.
Aug. 25: Court sentences Samsung's Lee Jae-yong to five years in prison on bribery conviction.
Oct. 13: Court approves the prosecution's request to extend Park's detention.
Oct. 16: Park rejects the trial in protest at her treatment and the court's decision on extending her detention. Park's legal counsel resigns en masse.
Oct. 25: Court appoints five public defense attorneys for Park.
Feb. 5: Appellate court metes out a suspended prison term for Samsung's Lee Jae-yong. Lee is released after a yearlong presentencing detention.
Feb. 13: Court sentences Choi to 20 years in jail and Lotte's Shin Dong-bin to 2 1/2 years in jail.
Feb. 27: Prosecutors demand a 30-year prison term and 118.5 billion won ($112 million) in fines for Park.
April 3: Court decides to allow live broadcast of Park's sentencing trial.
April 6: Court sentences Park to 24 years in prison and 18 billion won in fine.
June 14: Prosecutors demand a 15-year prison term over charges of taking bribes from the state spy agency and interfering in elections.
July 20: Court sentences Park to six years in prison for taking off-book money from the National Intelligence Service and orders her to forfeit 3.3 billion won. She was sentenced to two years for violating election laws.
Aug. 24: Seoul appellate court raises the sentence for Park by one year to 25 years in a massive corruption case that led to her removal from office. Choi Soon-sil, Park's long-time confidante, was sentenced to 20 years in prison.
Aug. 29 -- Supreme Court strikes down a lower court's rulings against Park. The top court ordered the lower court to handle Park's bribery charges separately from her other charges. It also sent back to the lower court the corruption cases involving Choi and Samsung's Lee. (Yonhap)