Pakistan's former ambassador to United States, Husain Haqqani, center, must stay behind high walls because he fears attack while facing treason charges. (Aamir Qureshi/AFP/Getty Images)

The ex-ambassador’s quarters, decorated in placid blue, lie behind a half-dozen security gates. Outside are pine-studded gardens to stroll in. He has left the compound only three times in six weeks.

It is a dramatic change of pace for Husain Haqqani, who two months ago darted about Washington as Pakistan’s envoy to the United States. Now facing a court investigation in connection with a memo that has roiled Pakistani politics and led to his resignation, Haqqani says he fears that leaving his guest suite at the prime minister’s residence would be to invite death on the streets of his own country.

“I could be killed by a suicide bomber for being an American lackey,” Haqqani said in an interview this week, referring to one common characterization of him here. “There’s so much hype against me that I could meet the fate of Salman Taseer.”

Taseer was a liberal ruling-party governor who was assassinated one year ago by his own police guard, who disagreed with the politician’s criticism of Pakistan’s controversial anti-blasphemy laws. The accusations circling Haqqani — that he committed treason by engineering a memo asking for American help to rein in Pakistan’s powerful military — provoke similar passions here, his supporters say.

Haqqani’s attorney has offered another reason he must stay inside: The fearsome Pakistani military intelligence agency, she said, might capture and torture him into giving a false statement. And so Haqqani confines himself to an official mansion, offering what might be the starkest illustration yet of the chasm between Pakistan’s embattled civilian government and the military it technically directs.

That gap has only widened as furor over the scandal, known here as “Memogate,” escalates, plunging this volatile nation into deeper crisis. It came to light three months ago when a Pakistani American businessman, Mansoor Ijaz, said he delivered the memo to Adm. Mike Mullen, then chairman of the U.S. Joint Chiefs of Staff, who has said he ignored it.

Ijaz later said he wrote the memo on Haqqani’s instructions. Haqqani has denied involvement, and many Pakistani observers initially expected his resignation to quell the commotion. That did not happen.

Officials from the ruling party and some analysts say the saga is aimed at bringing down Pakistan’s U.S.-backed government or triggering the impeachment of President Asif Ali Zardari, who is himself so unpopular that he rarely appears in public. Prime Minister Yousuf Raza Gilani has suggested a military plot is underway. But many — among them opposition politicians, sectors of the media and the military — are convinced Haqqani arranged the memo on Zardari’s orders, and they are doggedly pursuing the matter.

U.S. senators’ support

On Thursday, U.S. Sens. John McCain (R-Ariz.), Mark Kirk (R-Ill.) and Joseph I. Lieberman (I-Conn.) issued a statement condemning the “harassment” of Haqqani, whom they called a “principled advocate” for Pakistan.

As ambassador, Haqqani, a former journalist and Boston University professor, was a seemingly tireless man about Washington, combining seductive sound bites and scholarly analysis to crystallize Pakistan’s case on the Hill, in television interviews and at exclusive dinner parties. But in Pakistan, his deft handling of Americans — and his history of switching political sides — was viewed as suspect. Pakistan’s generals saw him as Zardari’s ambassador, not Pakistan’s.

The controversy has reached the Supreme Court, which is admired by many as the most independent in the nation’s history but is regarded by the ruling Pakistan People’s Party as a tool of the army and the opposition. After he returned to Pakistan in November to face questions over the scandal, the court banned Haqqani from leaving the country, although he has not been charged with a crime. Last weekend, the court appointed a fact-finding judicial commission to investigate the origin of the memo, which, among other things, promised to hand over terrorism suspects to the United States or allow U.S. forces to capture or kill them in Pakistan.

Haqqani’s attorney, prominent human rights lawyer Asma Jehangir, denounced the court for overstepping its boundaries and acting as an “acolyte” of the military establishment. She has refused to appear before the commission.

Babar Sattar, a constitutional law expert, said the court had acted appropriately and showed a rare willingness to take up a matter involving national security, an area long ceded to the military. But he and other legal experts questioned the court’s quickness, even as it allows other cases implicating the military establishment to languish.

“The criticism is that the judicial scrutiny is happening only because the military wants it to happen and that that’s not a level playing field for Husain Haqqani and Asif Ali Zardari,” Sattar said.

The civil-military divide is clear in affidavits presented to the Supreme Court. Government officials denied involvement and noted that a parliamentary committee was already probing the matter. But spy chief Lt. Gen. Ahmed Shuja Pasha said that Ijaz, during an October meeting in London, presented “enough corroborative evidence to prove” his story.

So far, the bulk of evidence has come from Ijaz, who released logs of what he says are BlackBerry message conversations between him and Haqqani. Haqqani’s attorneys say none directly refer to the memo.

‘What is all the fuss about?’

The scandal is distracting attention from graver national problems, some analysts argue, including shortages of gas used to heat homes and power cars, a faltering economy and regular insurgent attacks.

The memo “has led to no consequences for Pakistan . . . so what is all the fuss about?” said Ayaz Amir, an opposition politician who is critical of Haqqani.

The judicial commission is expected to report its findings to the Supreme Court at the end of January. At that point, the court could drop the matter, urge Parliament to pursue Zardari’s impeachment or order investigators to charge Haqqani with a crime such as treason, which carries the death penalty. Neither of the latter two options would proceed quickly, legal experts said.

Another possibility, viewed as remote, is that the commission could fault Pasha for traveling to meet Ijaz without the prime minister’s permission, Sattar said.

Haqqani, who has written critically about military dominance in Pakistan, said he is ready for a long stay at the prime minister’s residence. There, he greets a stream of visitors and sends e-mails energetically, just as he did as ambassador. He said he has left to go to the dentist, to meet his attorney and to testify before a commission examining the U.S. raid to kill Osama bin Laden.

Haqqani shrugged off the loss of liberty.

“If that’s all I wanted, I would have remained a correspondent or a professor,” he said. “You come into politics because you believe in something. In a country like this, you take risks.”