How did gangsters like Bonnie and Clyde and Al Capone escape from the police before bullet proofing their cars? And how did the bullet proof cars help them?

3 answers

As I recall, Bonnie and Clyde didn't escape. Al Capone didn't have much trouble with the police, he had them on his side for years. It was the Feds who got to Al. Cicero Illinois was run by Al, city government, police, and all. Read this interesting article.
http://en.wikipedia.org/wiki/Al_Capone

The bullet proof cars were often fitted with police sirens.
I'm not aloud to use wikipedia.
If you're not allowed to use Wikipedia, then go to that article bobpursley posted and check out the further references and external links at the bottom of the webpage.

=)