WASHINGTON — On the evening of Feb. 6, a vice mayor of a major Chinese city who had a reputation as a crime fighter turned up at the American Consulate in Chengdu in an agitated state, telling a tale of corruption and murder that has ensnared the Obama administration in a scandal it wants nothing to do with.
The official, Wang Lijun, sought asylum, fearing for his life even as Chinese security forces quickly surrounded the building and asked the American diplomats inside to turn him over.
Instead, after a frantic debate that reached the White House, Mr. Wang stayed until he could arrange for an official from a Beijing ministry to come 36 hours later and escort him past the local security cordon. The authorities from Beijing took him into custody, and he is now under investigation for divulging internal Chinese affairs to the Americans. If charged with and convicted of treason, he could face a death sentence.
The information Mr. Wang possessed involved Bo Xilai, who was the Communist Party chief in Chongqing until last month and Mr. Wang’s onetime patron before a falling-out led Mr. Wang to seek refuge in the consulate, according to administration officials, Congressional aides, diplomats and others briefed on what had happened.
According to the officials’ version, the American diplomats who oversaw his brief, bizarre stay pre-empted any formal application for asylum because of the difficulties of spiriting him out of the country and questions about his eligibility. Instead, they said, the State Department shielded him from almost certain arrest by police officers loyal to Mr. Bo and ensured he could make his accusations in Beijing.
Those charges brought down Mr. Bo and his wife, Gu Kailai, who is now under investigation in the murder of a British businessman, Neil Heywood, and involved the United States and Britain in the biggest scandal facing China’s leadership in a generation.
“He was not tossed out,” a senior administration official said, referring to Mr. Wang.
Some Republicans in Congress question, however, whether the Obama administration mishandled Mr. Wang’s case and left him to the mercy of the Chinese authorities when he had sought to pass along explosive information that affected a power struggle at the top of the Chinese Communist Party.
Mr. Wang’s arrival at the consulate could not have come at a more sensitive moment for the administration: just a week before China’s likely future leader, Xi Jinping, was scheduled to visit Washington at the invitation of Vice President Joseph R. Biden Jr. Granting asylum to Mr. Wang could have soured or scuttled Mr. Xi’s trip.
Even now, the episode — which one Congressional official described as “a ‘Bourne Supremacy’ plot” — risks straining relations as the White House hopes to manage China’s rise and enlist its support on issues like the nuclear ambitions of North Korea and Iran and the government crackdown in Syria.
As a result, the American role has been shrouded in silence. Officials at the embassy in Beijing, the State Department and the White House have declined to comment publicly on Mr. Wang’s contacts with American diplomats or the implications of his whistle-blowing on China’s suddenly turbulent internal politics.
“It would be incredibly foolish for the U.S. to play any public cards in this very messy Chinese family feud,” said Orville Schell, the director of the Center on U.S.-China Relations at the Asia Society. “The U.S. and China urgently need to get along, and if there is one thing the Chinese are neuralgic about, it is when their private affairs get aired before foreigners in an embarrassing way.”
The chairwoman of the House Committee on Foreign Affairs, Representative Ileana Ros-Lehtinen, Republican of Florida, wrote to Secretary of State Hillary Rodham Clinton in February demanding the release of all cables, e-mails and memos related to the case. The circumstances, she wrote, raised question about “what steps were taken to secure U.S. national interests and Mr. Wang’s personal safety.” The State Department has not yet complied.
According to the State Department, the United States cannot simply grant asylum to anyone who walks into a diplomatic compound, given the legal and logistical complications of spiriting someone out of a sovereign nation. Asylum seekers — who typically face persecution for political or religious beliefs — usually apply outside their own nation, whether in the United States or a third country.
There are exceptions, but they are rare.
In June 1989, the Chinese dissident Fang Lizhi walked into the American Embassy in Beijing a day after security forces attacked protesters in Tiananmen Square. The embassy at first resisted, but the administration of President George Bush offered him sanctuary, provoking a standoff that lasted a year until the Chinese allowed him to leave, ostensibly for medical treatment. (Mr. Fang died in Arizona on April 6; he was 76.)
This case, however, differs significantly. Mr. Wang, a vice mayor in Chongqing who had overseen the police before a falling-out with Mr. Bo, is no political dissident. During his years as one of Mr. Bo’s top aides, he had a reputation in Chongqing for ruthless and arbitrary enforcement of the law.
That made a decision on asylum all but impossible, the diplomats felt, according to one official briefed on the case, who like others would speak only on condition of anonymity. He and others said the State Department, after informing senior White House officials about Mr. Wang, had avoided that sticky question from that start by facilitating Mr. Wang’s transfer to Beijing. The decision to proceed that way was made by the State Department, those who were briefed said, not the White House officials, whom they declined to identify.
“Granting asylum to a major human-rights icon in China, during the midst of the Tiananmen Square uprising, is a special case,” said Jeffrey A. Bader, a former China policy adviser to President Obama. “It should not be seen as a precedent, especially in the case of a former provincial police commissioner, with hundreds of Chinese security forces assembled outside the consulate.”
The consulate in Chengdu, with roughly 30 American officials, oversees visas and commercial affairs for southwestern China. The consul general, Peter Haymond, was not in Chengdu at the time, officials said, leaving Mr. Wang’s case to subordinates. They alerted the embassy in Beijing, which flagged Washington.
Mr. Wang arrived with documents detailing accusations against Mr. Bo and Ms. Gu, but he did not hand them over, the American officials said. The contents are not known, though one official described them as technical descriptions of police investigations in Chongqing. Mr. Wang was allowed to make phone calls to officials in Beijing he hoped would help him. In the meantime, he regaled startled diplomats with a rambling but ultimately revealing discourse on the murky intersection of power, politics and corruption in China.
“Not everything was coherent, as you would expect,” a Congressional official said, “but he did provide some good insights.” As Kenneth G. Lieberthal, a former China adviser in the Clinton administration, put it: “Two things were clear the moment he walked in: this was a very big deal, and this was a very unsavory character. This is not the Dalai Lama who walked in the door.”
Sharon LaFraniere contributed reporting from Beijing.
This article has been revised to reflect the following correction:
Correction: April 17, 2012
A previous version of this article stated that Gu Kailai was charged with the murder of Neil Heywood. Ms. Gu is under investigation for the murder, and has not yet been charged.