Media outlets reported last May that Firefighter Charles Anthony MacDougall survived the attack at the Cecil Hotel while assisting a man in distress, but detectives found inconsistencies in the story.
Despite the allegations, MacDougall will not face charges after prosecutors determined they could not move forward with a criminal case due to a lack of evidence.
The ten-year department veteran has been on paid administrative leave since last summer.
City attorney spokesman John Franklin would not say not say how the stab wounds might have been inflicted or what details led officials to believe he lied, according to the report.
MacDougall's partner -- who also was put on administrative leave -- told police that he came out of the hotel's coffee shop and told him that a person needed to be examined and reentered the hotel alone.
The partner eventually went upstairs to find MacDougall bleeding from stab wounds.
