(Bo Xilai and his wife Gu Kailai in a 2007 file photo. | AP)

Gu Kailai, the wife of deposed Chinese Politburo member Bo Xilai, was treated for severe depression for the past several years, according to three close family associates, who said the family hopes Gu can be given a mental health evaluation before she stands trial on charges of murdering a British businessman.

The associates said Gu — a Peking University-trained lawyer — spent the past three years largely as a recluse, rarely going outside and never traveling abroad. They said Gu’s mother, 90-year-old Fan Chengxiu, lived with Gu most of that time in Chongqing, where Bo was the high-flying Communist Party chief, presiding over a booming provincial economy and a controversial crackdown on organized crime gangs.

The individuals who gave this information spoke on the condition of anonymity because of the extreme sensitivity of talking with the foreign media and fear of retribution.

Gu and a household aide, Zhang Xiaojun, have been charged with murder for allegedly poisoning British businessman Neil Heywood in November after a falling out over a business deal. They will be tried in a court in Hefei, in Anhui province, possibly in early August, family associates said.

Bo saw his political ambitions swiftly collapse after the death, as he was removed from the job in Chongqing and stripped of his party positions. He now is under house arrest, awaiting word of his fate.

The operatic-like downfall of one of the communist hierarchy’s most prominent power couples has gripped China and disrupted the party’s plans for a drama-free transition later this year to a new leadership team headed by Vice President Xi Jinping. Until his fall, Bo — like Xi, the “princeling” son of a famous revolutionary-era father — was considered a shoo-in for a promotion to the powerful Politburo Standing Committee, which effectively runs the country.

The charismatic Bo garnered an unusual degree of popular support in China, where most leaders remain faceless and prefer cautious anonymity. There is a widespread belief here that Bo was removed not because of the allegations against his wife and aide, but because his popularity and leftist policies — such as regularly denouncing the country’s growing income disparity — threatened the ruling elite’s sense of harmony.

The Chinese government, through its official media, has tried to keep attention focused on the death of the Briton, insisting that the trial will be fair and show that no one is above the law. Bo has not been charged with any crime in the case.

But Gu’s family members have questioned whether her trial will be fair, and they have criticized the government for refusing to allow the family to choose two well-known Beijing lawyers to represent her. Instead, Gu will be represented by two government-appointed lawyers from Anhui province.

Forcing criminal defendants to take government-appointed lawyers is a common tactic in politically charged cases in China, even though lawyers say it violates China’s laws allowing defendants to choose. Critics say the practice opens the door for a swift and hassle-free conviction.

“This kind of practice violates the law,” said Mo Shaoping, a Beijing criminal lawyer not involved with the Gu case. But, he said, “it’s a common practice, especially with sensitive cases. The government prefers these pro-government lawyers, who are more easily controlled.”

The two Beijing lawyers hired by Gu’s family, Shen Zhigeng and Du Lianjun, said they are neutral on whether Gu is guilty or innocent of the crime because they have not been allowed to see evidence or meet with Gu in Anhui, according to the three associates with firsthand knowledge of the case.

But the family associates said Gu’s mother, Fan, remains convinced that Gu is innocent in the poisoning death of Heywood because Gu had neither the financial motive nor the mind-set. “Mrs. Fan can’t believe her daughter committed such a crime,” one associate said. “In her mother’s eyes, she’s very kind and sympathetic. Most importantly, her daughter didn’t have any motive for murdering Heywood.” The associate said Gu had not seen Heywood for several years.

“Gu Kailai has suffered from psychological problems for years,” said one family associate who has direct knowledge of the situation. “She’s had serious depression for four or five years. In the past three years, Gu Kailai spent most of the time with her mother, almost every meal. Gu Kailai didn’t work, and didn’t contact anyone outside. . . . She spent most of her time in treatment all these years.”

This family associate said Gu gave up her lucrative law practice so as not to be an impediment to her husband’s political ambitions. He claimed Gu jealously guarded Bo Xilai from favor-seekers, including family members, who wanted to cash in on his rising star in the Communist Party. The associate also said Gu often felt hurt that she was misunderstood and cast in the public mind as wealthy or conniving. He recalls Gu once complaining, “I live in a glass house, and everything is in the public eye after I married Bo Xilai.”

Family members are denying widespread overseas media reports that Bo and Gu had amassed a fortune abroad, sometimes estimated as tens of billions of dollars. They said most of the tuition fees for their son Bo Guagua — who was educated at expensive schools including Oxford in England, and Harvard University’s Kennedy School of Government — was paid for with money Gu borrowed each year from one of her sisters.

Fan, Gu’s mother, returned to Beijing from Chongqing on April 20, weeks after Gu was taken away by authorities. Gu is believed to be under house arrest in Anhui province.

“If they can treat a senior party member like this,” Fan, a party member for 75 years whose husband was Mao-era revolutionary Gen. Gu Jingsheng, said to family associates, “how will they treat ordinary people?”