By Benjamin Kang Lim and Ben Blanchard
BEIJING (Reuters) - Chinese President Xi Jinping secured the blessing of his still influential predecessor, Hu Jintao, before launching a corruption probe against a former senior aide to Hu - a sign that internal Communist Party harmony and respect for elders still holds sway in Xi's historic crackdown on official graft.
Hu signed off on the probe into disgraced former aide Ling Jihua, who is suspected of trying to cover up his son's death in a luxury sports car crash two years ago, people with ties to the leadership said.
The party announced last week that Ling was being investigated for "suspected serious discipline violations" - the usual euphemism for graft. It gave no other details.
"In investigating Ling, Xi was not targeting Hu," one individual with ties to the leadership told Reuters. "Hu did not (try to) block the investigation. He agreed to and supported it when consulted."
Hu stepped down as party and military chief in 2012 and as state president the following year in the first clean handover of power since the People's Republic of China was founded in 1949.
Ling was first demoted in September 2012 after sources said his son was involved in a fatal crash involving his Ferrari sports car in Beijing six months earlier.
The incident was an embarrassment for the party, which is sensitive to perceptions that children of top party officials lead rich, privileged lifestyles completely out of touch with the general population.
Ling is suspected of unilaterally mobilizing the party's Central Bodyguards Bureau and trying to cover up his son's death, the sources said. "Ling failed to control his wife and son," a second person said, referring to Chinese Internet reports of scandals implicating Ling's wife.
Ling was dropped from his post as head of the party's General Office of the Central Committee, a powerful post similar to cabinet secretary in Westminster-style governments, following the crash. He was then appointed as minister for the less influential United Front Work Department, which is in charge of co-opting non-Communists, religious groups and ethnic minorities.
On Tuesday, state media said Sun Chunlan, a rising star in the party who had been party boss of Tianjin and is one of China's few senior female politicians, would become the new head of the United Front.
However, Ling is still shown as one of the deputy heads of the Chinese People's Political Consultative Conference, a high-profile but largely ceremonial advisory body to parliament, on its website.
CE Weekly, a news website run by the party's official People's Daily, on Monday ran a long story on Ling and his family, and made a rare mention of the car accident in which his son died. The story was picked up more widely by Chinese media on Tuesday.
The website said Ling went to work as normal the day after the crash, adding there were also two women in the car who were injured and in a "state of partial undress".
"The death of his son really affected his mental state," said a third individual. "Ling had been thought of before as an upright official."
It was not possible to reach Ling for comment and it is not clear if he has a lawyer.
Speculation about Ling's fate had been running high after a probe into his older brother, Ling Zhengce, was announced in June for suspected "serious discipline and law violations". After Ling Zhengce fell, the official Xinhua news agency noted cryptically that "having somebody in the palace won't help", in pointed reference to his family connections.
China's campaign against official corruption has intensified since Xi took over as president, with several senior government figures and state company executives in detention, including the powerful former domestic security chief Zhou Yongkang.
(Editing by Ian Geoghegan)