According to the article at least (which has been pointed out to be one-sided), at least one of the officers empties the first magazine and reloads. This would

According to the article at least (which has been pointed out to be one-sided), at least one of the officers empties the first magazine and reloads. This would be 15-17 for the first officer, and the article also notes that the second car arrived after the shooting begun. I don't know everything that happened, and haven't developed an opinion overall, but it isn't as simple as rounds fired / number of officers.