1998 Prison Sentence and Escape On 12 March 1998, Sonko was convicted in two separate cases for failure to appear in court. In one case he was fined KSh 200,000 or 6 months in prison; in the other case a fine of KSh 500,000 or 6 months. Because he didn't pay the fines, he was to serve prison time. These sentences were to run concurrently, giving a 12-month term, to be served at Shimo La Tewa Prison. On 16 April 1998, Sonko reportedly served about one month of the sentence, then “mysteriously” left Shimo La Tewa. He was reported to have been admitted for treatment at Coast General Hospital, and from there is said to have escaped custody. The prisons authorities later said that he should be charged with escaping from prison and should serve his remaining sentence. He was reported to have assaulted 9 individuals together with goons in the 2019 property raid. In March 2024 the case was withdrawn.
Corruption charges 357 million graft case On 6 December 2019, the Director of Public Prosecutions in Kenya issued an arrest warrant against Mike Sonko for various corruption charges during his tenure as a Governor of Nairobi County. He was arrested in
Voi. After the arrest, he was detained at
Kamiti Maximum Security Prison for a few days and released on December 11, 2019, by anti-corruption court for a bond of Sh30 million or a surety of the same amount or a cash bail of Sh15 million. As a condition for the release, he was barred from accessing office of
Nairobi County governor until the case was determined. The Senate impeached him on 17 December 2020.
24 million graft case In December 2019, Sonko was accused of
extortion of Ksh 10 million to facilitate payment to a software company while he was governor of Nairobi. He was charged with abuse of office and conflict of interest. In January 2025, a high court ruled that Sonko has a case to answer in the 24 million graft case. His
acquittal in the case was set aside and a new trial ordered under another magistrate.
20 million graft case In January 2020, Sonko was charged with
money laundering, conflict of interest, fraudulent acquisition of public property, and conspiracy to commit an offense of corruption. In December 2022, Sonko was acquitted by a magistrate's court due to defective charges. In December 2024, a high court overturned Sonko's acquittal in the matter due to reliance on an old charge sheet instead of an amended charge sheet.
US Travel ban Due to involvement in corruption, the U.S. Department of State designated him and his wife Primrose Mwelu Nyamu Mbuvi; their daughters Saumu Agnes Mbuvi and Salma Wanjiru Mbuvi, and Sonko's minor child in March 2022 as ineligible for entry into the United States. ==Personal life==