About Accused: Guilty or Innocent? Season 3, Episode 10 : Murdered My Tenant or Self-defense?

When a landlord shoots a problem tenant dead in Florida, police and prosecutors act swiftly--charging the landlord with murder. The landlord claims that the tenant was carrying a machete at the time of the shooting and threatened to kill him. With the landlord facing life in prison if found guilty, is this self-defense or murder?