A combination of two photographs shows British businessman Neil Heywood and Gu Kailai, wife of China's former Chongqing Municipality Communist Party Secretary Bo Xilai. Cold-blooded killer or scapegoat, Gu Kailai remains an enigma as she is tried for murder in a case that has shaken the ruling Communist Party and placed its secretive world of political privilege under intense scrutiny. (Reuters)

The murder trial of Gu Kailai, the wife of deposed Communist Party official Bo Xilai, that opened Thursday marks the beginning of the Chinese ruling party’s attempt to close the chapter on one of its most divisive and embarrassing episodes in recent memory.

The six-month saga surrounding Bo and his wife — including lurid allegations of corruption, murder and intrigue involving senior members of the Communist Party’s “red aristocracy” — opened a rare window onto the normally secret world of China’s elite politics. Now, with a leadership transition pending this fall, all evidence suggests the party wants the Bo affair settled, and quickly, so it can repair the damage and move on.

The much-anticipated trial opened Thursday under tight security at the intermediate court in Hefei, the capital of Anhui province. Police barricaded the street leading to the courthouse, turning back all cars and buses. And the courthouse itself was ringed by police standing every few feet, and shoulder to shoulder up the main steps. A throng of journalists and onlookers was kept outside in a driving rainstorm. Around 9 a.m., two apparent supporters of Bo were quickly hustled away by police when they began shouting slogans.

Gu and a household aide, Zhang Xiaojun, have been charged with murder in the poisoning death of a British businessman, Neil Heywood, with whom Gu allegedly had a business dispute. Bo has not been charged with any crime but was removed from all his party posts in the spring for unspecified “discipline violations.”

Gu’s conviction is considered a foregone conclusion in China, where the police, courts and prosecutors operate under the party’s tight control and largely according to script. But the evidence presented in court, any witnesses allowed to speak and the severity of the eventual sentence that Gu receives will all signal how the party intends to handle Bo.

Bo, the charismatic son of a Mao-era revolutionary hero, is still thought to command a following in China, particularly among the “new leftists” disenchanted with the country’s growing income disparity and the loss of socialist ideals. Some analysts say that the party’s senior leaders, who are meeting now for their annual summer retreat at the Beidaihe seaside resort, remain deeply divided over what punishment Bo should face.

On the one hand, observers say, some want Bo not only stripped of his party positions but also jailed on criminal charges, to preclude any chance of a comeback by a figure who had become a danger because of his populist appeal. “He may come back to politics,” said Cheng Li, a China scholar with the Brookings Institution in Washington. “It’s in everyone’s interest to punish Bo severely.”

But Bo is said to still have allies, who think he should face a milder internal party discipline, equivalent to a censure, particularly if there is no evidence that he had a hand in Heywood’s slaying or knew anything about it.

“It’s a question of how to settle this problem after ousting him,” said Bo Zhiyue, who is a senior researcher with the National University of Singapore and not related to Bo Xilai. “It’s not just him. He represents a trend of thought in society,” such as favoring a more equitable distribution of wealth. “A lot of senior party members agree with this idea. Bo Xilai still has a lot of political resources, like his personal relationships among the princelings and in the army. . . . He still has a lot of influence, and supporters in the party. So it will be hard to completely defeat him.”

“They’re facing a deadlock on how to deal with Bo,” he added. “If they can take Bo down permanently, everyone will follow along and the party can avoid breaking up. Otherwise, the party’s unity will be in jeopardy.”

Bo’s fate is likely to be decided at the party’s secretive conclave at Beidaihe. Gu’s future, meanwhile, will be determined by the court in Anhui province, far from the site of the alleged crime.

It is likely to be China’s most closely watched trial since the Gang of Four were put on courtroom display in 1981. That case, involving Mao Zedong’s widow, Jiang Qing, was broadcast on state television as a public signal to the Chinese people that the Cultural Revolution led by Jiang and her cohort was over.

By contrast, Gu’s trial will be held mostly behind closed doors, with limited seats available for journalists, despite intense public and media interest. British diplomats have also been given permission to attend because of Heywood’s nationality.

The court said that Gu’s family, and the family of the household aide, Zhang, could each have two representatives attend. Both families had hired Beijing lawyers to assist with the cases, but the court refused to accept them, appointing local Anhui lawyers instead.

Earlier this week, some outlines of the defense began to appear, with associates of the Zhang family who had knowledge of the case saying that Zhang did not know Heywood and had no motive for killing him. Zhang was only following Gu’s orders, the associates said, and Zhang said he was not the one who carried out the killing.

The associates described Zhang, 33, as intensely loyal to Gu, having served in the military briefly as an orderly for her father, the late Gen. Gu Jingsheng. A family associate said Zhang had “cooperated” with the government by accepting its appointed lawyer, and in a letter to his family he expressed confidence that he would be home soon with his wife and infant son.

Legal experts in Beijing who are not involved with the case said it was common in murder cases for defendants treated as accomplices — who did not commit the actual killing — to receive lighter sentences.

Meanwhile, Gu’s family members complained that Gu was being treated unfairly and not allowed to have her own lawyer from Beijing. The family members said Gu had been suffering from depression for years and rarely left her home.

Zhang Jie in Beijing contributed to this report