The Waimate Conspiracy 2006 one on netflix

The 2005 discovery of a cannonball, buried for 138 years in a paddock, throws Waimate into turmoil. It is all the Maori locals need to confirm their long-held belief that they were forcibly removed from their tribal lands, in a bloody 1866 battle. The hotly contested claim eventually ends up in the District Court and on the lens of cameraman Dave who captures all the arguments, frauds and forgeries of the townspeople, in a cinema verité mockumentary style.