That's one of those 'odds' questions that is interesting to speculate about.  When someone is killed or injured by either the speeding car or use of the illegal firearm, however, the 'odds' don't really matter to the person who was injured or killed.  Then we will have the absolute certainty of the armchair police officers with 20-20 hindsight that the other possibility was the proper choice.  And we will also be guaranteed the views that "the police are all intentional killers" contrasted by those who assert that "the police can do no wrong".   I can predict the names on these threads for both of those positions right now.