The tour operator was found guilty of attempted murder last week.
Mboya was accused of attempting to kill Osewe and another man, Wilfred Ombunya Tembula, on December 1, 2016.
The court heard that Mr. Mboya shot and left Mr. Osewe several times for dead.
Milimani chief judge Martha Mutukusa said the prosecution led by Anderson Gikunda was overwhelming Presented evidence justifying a conviction.
“It is undisputed that Mboya shot Osewe. He did this not once, but four times,” said the judge.
Mboya denied charged with attempted murder in 2017 and was released on bail of 300 shutters. 000.
In 2019, however, he admitted to having shot the restaurateur, but argued that this was done in self-defense after Osewe threatened him.
In his mitigation, Mboya, through Attorney Benjamin Makokha, advocated a non-custodial sentence, saying that this would not amount to condemning the society that depends on him.
“My client is a polygamous family with several children who are Survival depends on him, “said Mr. Makokha.