Kurmanbek Bakiyev was ousted from power in a mass uprising in 2010 stoked by indignation over stagnant economic progress and rampant corruption.
He fled to Belarus, where he now lives under the auspices of its authoritarian President Alexander Lukashenko.
Kyrgyzstan has seen the overthrow of two governments in its short history since gaining independence amid the collapse of the Soviet Union in 1991.
President Askar Akayev was cast out of power in May 2005 after a weeks-long sit-in protest against corruption and misrule in the center of the capital. Five years later, several dozen people were shot dead by government troops when angry mobs attacked the presidential administration building in unrest that led to Bakiyev's ouster.
The constitution introduced in 2010 created a more even balance of power between parliament and the presidency, aimed at avoiding the emergence of an authoritarian leadership.
Jill Lawless in London contributed to this report.