While making their escape the robbers forced Coleman to the ground, injuring his shoulder. Shots were exchanged between Coleman and the suspects -- though no one was hit.
Coleman told investigators a masked man held him at gunpoint during the crime, but prosecutors said he actually helped plan the robbery with two other people after phone records indicated he had spoken with one of the suspects just before the robbery.
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Coleman had been with the Dallas police for four years and had no prior disciplinary issues.