The United Nations Human Rights Council Working Group on Arbitrary Detention (UNWGAD) has found that the detention of Tanzanian opposition leader Tundu Antiphas Mughwai Lissu is arbitrary under international law.
The working group’s Opinion No. 74/2025, issued on February 23, 2026, calls on the Government of Tanzania to release him immediately and provide compensation and other reparations.
Mr Lissu, the national chairperson of Tanzania’s main opposition party, CHADEMA, has been imprisoned since April 9, 2025, facing treason charges.
His arrest followed a public rally where he called for electoral reforms ahead of the country’s general elections in October 2025.
The UNWGAD’s decision concludes that Mr Lissu’s deprivation of liberty contravenes multiple provisions of the Universal Declaration of Human Rights and the International Covenant on Civil and Political Rights, to which Tanzania is a party.
The working group found the detention to be arbitrary under four distinct categories:
- Category I: No legal basis for the detention.
- Category II: The detention results from the exercise of fundamental rights, such as freedom of expression and assembly.
- Category III: Serious violations of the right to a fair trial.
- Category V: The detention is discriminatory, based on political opinion.
The UN body highlighted that the reliance on a non-bailable treason charge without an individualised assessment of its necessity is incompatible with international human rights law.
It also pointed to serious due process violations, including interference with lawyer-client communications and obstacles to public access to proceedings.
Robert Amsterdam, whose firm Amsterdam & Partners LLP submitted the application to the UNWGAD, stated, “The United Nations Working Group has issued a decisive finding: Tundu Lissu’s detention is arbitrary and unlawful under international human rights instruments. The appropriate remedy is immediate release, compensation and other reparations, and an independent investigation into how this abuse occurred.”
The UNWGAD has requested the Tanzanian government to provide information within six months on the implementation of its recommendations, including Mr Lissu’s release, reparations, and legal reforms.
READ MORE: Tanzania’s Opposition Leader Tundu Lissu Wanted Reforms. The Govt Gave Him Treason Charges
Coinciding with the UNWGAD’s announcement, a Tanzanian delegation led by the Minister for Constitution and Legal Affairs, Dr Juma Zuberi Homera, arrived in Geneva to participate in the High-Level Segment of the UN Human Rights Council. The delegation is expected to present a report on the human rights situation in Tanzania.
Mr Lissu, a vocal critic of the government, survived an assassination attempt in 2017 when he was shot 16 times.
His arrest in 2025 has been condemned by human rights organizations, which have called for his immediate and unconditional release, citing a growing crackdown on opposition leaders ahead of the general elections.
