Sossion is a nominated member of parliament representing workers' interest in the National Assembly and has been active in educational matters since he started teaching in 1993, at Tenwek High School, in Bomet.
He has been passionately fighting for the rights of teachers.
He stepped down as KNUT Secretary-General on June 25, 2021, after serving in the position since 2013.
During his resignation, Sossion stated that his decision to resign from the union was to prompt the government to support teachers financially.
“There has been this argument that as long as Sossion stays the government will not release union dues. I’m making this passionate appeal that the government will find it necessary to allow union dues to flow to KNUT so that the leadership and workers earn a salary,” Sossion stated.
Being the sixth secretary-general of KNUT, Sossion ensured that during his era, public schools registered a better performance, compared to the previous years.