Joseph Kori has been released after the police failed to find evidence to linking him to the death of his wife Mary Wambui Kamagara.
According to police sources, Kori was released from Gigiri Police Station on Thursday night.
Officers from Department of Criminal Investigations (DCI) confirmed that he did not spend the night at the cell.
A Kiambu court had on February 13 allowed the DCI to hold Kori, his mistress Judy Wangui and a taxi driver Michael Mathenge.
They were held in custody for 14 days to allow for further investigations.
The other two suspects are still in police cells.