This video image taken from CCTV shows Gu Kailai, center, the wife of Bo Xilai, standing trial in the Intermediate People's Court in the eastern Chinese city of Hefei Aug. 9, 2012. (AP/AP)

China’s most widely anticipated trial in a generation ended Thursday less than eight hours after it began, with Gu Kailai — a daughter of the Communist Party’s “red aristocracy” and the wife of deposed charismatic leader Bo Xilai — confessing that she poisoned a British businessman who she believed threatened her son, according to an inside observer’s courtroom account.

The observer’s account, buttressed by an official court statement, detailed a dramatic case — including an e-mailed threat purportedly from the victim, Neil Heywood, and a description of how Gu poured a concoction of cyanide into Heywood’s mouth after he became drunk, vomited and asked for water. Finally, the observer said, Gu stood and addressed the court.

“I committed a crime that brought negative consequences to the party and the country,” Gu said, according to the courtroom spectator, a close associate of the defendants who spoke on the condition of anonymity because of the sensitivity of the case. Gu thanked her lawyers and the judge, as well as the prosecutors, who she said “opened the curtains a little bit, to reveal the hidden dirty secrets.”

Gu said calmly that she was ready to face her punishment, according to the courtroom observer, and asked for leniency for her loyal household aide, Zhang Xiaojun, who was also present. Prosecutors said that Zhang helped her carry out the murder but that Gu was the principal offender.

The case sparked China’s most serious political crisis in decades, derailing the expected promotion later this year of Bo. It also provoked anger among Bo’s many supporters and revealed long-
hidden fissures in the top ranks of the Communist Party’s normally secretive hierarchy.

With the swift trial of Gu — and a sentencing decision expected at a later date, following China’s ­usual practice — the party seems eager to move past the episode before a crucial leadership transition due later this year.

The trial was held in Anhui province, hundreds of miles from Chongqing, where the murder occurred. The only reporters allowed inside were from the state-run Xinhua News Agency and CCTV, typical for sensitive cases in this tightly controlled Communist country. Chinese media outlets relied solely on the Xinhua version of the trial, a terse dispatch based entirely on the official court statement, which provided few details about the proceedings.

In Chinese courts, unlike those in the United States, defendants often enter no plea. Instead, prosecutors outline their evidence and defendants are given a chance to speak — to rebut the charges, offer a competing narrative or suggest mitigating factors. In Gu’s case, the bland court statement said she “did not contest” the prosecution’s case. However, the courtroom observer went further, saying in an interview that Gu confessed.

The court statement said that Gu — who according to close family associates has suffered from severe depression in recent years — was not mentally stable at the time of the murder and that “her self-control was weaker than a normal person’s.”

According to the person inside the courtroom, prosecutors described how on Nov. 10 Heywood sent an e-mail to Bo and Gu’s only son, Bo Guagua, who was attending Harvard University’s John F. Kennedy School of Government. The prosecution said Heywood was upset over a property development deal that went bust and demanded that Bo Guagua, who introduced him to the project, send him 10 percent of the promised returns, about 13 million British pounds ($20 million), according to this account.

A copy of Heywood’s purported e-mail, written in English, was displayed in court with a Chinese translation, the person attending the trial said. According to the Chinese translation, Heywood supposedly warned Bo Guagua that if he did not pay the money, “you will be destroyed.” There was no verification that Heywood actually wrote the e-mail.

The prosecution said Zhang, the aide, told Gu about the threat, because Gu apparently did not use e-mail, the observer recounted. Prosecutors said Gu then asked Heywood to travel to Chongqing to meet, and, on Nov. 13, Zhang escorted the Briton from his home in Beijing to Chongqing’s Nanshan Lijing Holiday Hotel, a resort with spacious villas.

Gu had already prepared a poison concoction, after having a local party official search various vendors to find one who sold rodent poison containing cyanide, the courtroom attendee said, quoting the prosecution. The vendor who sold the poison was also arrested, the observer said in recounting the testimony.

The attendee and the official court document said that Gu instructed Zhang to carry the poison to the villa, and that Gu and Heywood first met there alone, drinking from a bottle of Royal Salute whiskey until Heywood became drunk and sick. Gu telephoned Zhang to come inside. When Zhang entered, Heywood, who had fallen down, vomited, soiling Zhang’s shirt, and then Heywood asked for water. Zhang helped Heywood into bed, Gu poured the poison mixed with water into his mouth and they left, the prosecution said, according to the court observer.

The court then heard how, the following day, Gu met with Wang Lijun, the police chief and deputy mayor of Chongqing and the right-hand man of Gu’s husband, Bo Xilai. Prosecutors said Gu confessed to Wang in that meeting but did not know that he was secretly recording their conversation.

Wang kept not only the recording but also blood samples taken from Heywood’s heart, the courtroom observer quoted prosecutors as saying. Wang had local police laboratories test Heywood’s blood twice for traces of poison, but the results were negative, the court heard.

In February of this year, Wang had a falling out with Bo Xilai over the Heywood case and fled to the neighboring city of Chengdu, where he took refuge for 24 hours inside the U.S. Consulate until he was escorted to Beijing by intelligence officers. Wang has not been heard from since.

Almost all the evidence presented in the court came in the form of written testimony that was read aloud. The only witness to testify in person was a scientist from China’s Ministry of Public Security — seen on CCTV in a short-sleeved white shirt with red necktie and eyeglasses — who said he tested Heywood’s blood in April. That test confirmed the presence of poison, the observer said.

Defense attorneys raised other possibilities for Heywood’s death, suggesting that perhaps he had a heart attack or that someone else was involved, the observer said. The official court statement said defense attorneys also argued that Heywood deserved “some responsibility” for his own murder because of the threat to Bo Guagua.

The Xinhua News Agency said 140 people attended the trial, including relatives and friends of Gu and Zhang, members of China’s legislature and two British diplomats. Also inside was a representative of Heywood’s family, who asked the court to consider civil compensation in addition to any prison time for Gu and Zhang.

In addition, court officials announced that four Chongqing policemen will be put on trial Friday for trying to help Gu cover up the crime, the first official notice that more people may have been involved in Heywood’s death and the subsequent coverup.

Zhang Jie in Hefei contributed to this report.