18-year-old Joseph Fowler is charged with manslaughter for the shooting death of Michael Huffman.
Police say Fowler was handling a loaded gun back in January of 2011 when the gun went off, shooting Huffman.
It happened at a west Abilene mobile home park.
Fowler told police that he, Huffman and another teenager were playing Russian roulette with the gun.
The trial is scheduled to resume Friday afternoon with the testimony of a ballistics expert.
The trial is being conducted without a jury.
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