Antoinne Bethea, 41, is accused of killing 36-year-old Terrance Sr. of New Orleans.
Durrel was the father of Bethea's girlfriend's child.
They got into an argument on Easter in 2017 at an apartment on Ohio Street in Bangor and gunfire erupted.
Durrel was hit and died. Bethea eventually was arrested during a traffic stop in Ohio after he fled Maine.
Bethea has pleaded not guilty and claims the shooting was in self-defense.
The trial will get underway following jury selection. which begins on Wednesday. .