[6] After his departure from Milongo's transitional government, Mbemba again practiced as a lawyer from July 1992 to October 1997, in addition to his political activities.
[1] Following the June–October 1997 civil war, in which Lissouba was ousted, Mbemba was appointed as Minister of Labour and Social Security by President Denis Sassou Nguesso on 2 November 1997.
[7][8] In March 1998, "armed bandits" wounded Mbemba during an invasion of his home, while also killing a bodyguard and driver.
[11] Following that election, he remained Minister of Justice and was additionally assigned responsibility for human rights in the government appointed on 18 August 2002.
[20] Sassou Nguesso instead appointed Mbemba as a member of the National Commission of Human Rights, a constitutional body, a few days later.
[21][22] In 2013, Mbemba was investigated by the Directorate for Territorial Surveillance regarding allegations of "possession of weapons of war and attempted destabilization of national institutions".
In protest, the UP announced on 19 June 2013 that it was suspending its participation in the Rally of the Presidential Majority (RMP) coalition.