[3]) is a politician in Papua New Guinea who was elected President of the Autonomous Region of Bougainville in 2008 following the death of Joseph Kabui while in office, serving the remainder of the term from 2009 to 2010.

[2][5] The Bougainville independence movement began in the 1980s after local landowners closed the Panguna copper mine.

Tanis' predecessor, John Tabinaman, took over as Acting President after Joseph Kabui died in office of a heart attack in June 2008.

[12] Before the inauguration, Tanis undertook a trip through some twenty fast flowing rivers and creeks before arriving safely in Arawa for the ceremony.

In March 2019 Tanis was dismissed from office, having been found guilty by an independent Board of Inquiry of gross misconduct.

Despite this, Tanis is quoted by media as saying he had already been appointed as a special envoy of President John Momis on Peace.