Musharraf could also face a host of legal dangers.
The Supreme Court, headed by the chief justice Musharraf tried to dismiss, has declared his 2007 imposition of emergency rule unconstitutional, which could be a basis for actions against him.
Polls show that Nawaz Sharif, the prime minister Musharraf ousted in 1999, is Pakistan's most popular politician and he too has called for Musharraf to be put on trial.
Musharraf left Pakistan about a year ago and spends most of his time in Britain and the United States.
Many Pakistanis welcomed the 1999 coup by the straight-talking army chief, which ended a decade of fractious rule by rival parties tainted by corruption accusations.
But the longer he ruled the more unpopular he became.
He tried to strike a power-sharing deal with Benazir Bhutto, a former prime minister, who returned from self-exile in October 2007 to campaign for a general election. But she was assassinated weeks later.
Musharraf's government said Pakistani Taliban were responsible but in a country where conspiracy theories run rife, many people believed shadowy forces, perhaps close to Musharraf, played a part in her death.
The party that backed Musharraf was humiliated in a February 2008 election, in which Bhutto's party won the most seats, and Musharraf stepped down later that year.
He survived two bomb attacks and officials spoke of other plots to assassinate him.