Who started SB 1070 anyway?

An NPR story covers who started SB 1070:
http://www.npr.org/templates/story/story.php?storyId=131191523

Just in case you don't have 30 minutes to read or listen to the story, here's the summary of it:
A "subtle pattern of influence that helped this bill along from the very beginning" came from the private prison industry.

From a paper written by one of my best friends last week:
"The problem is that crime has actually decreased in Arizona and many other states, so if these companies are to continue to increase revenues, they must find new prisoners (Hodai, 2010). The source for these new prisoners is illegal immigration." (citation not included to protect privacy)

So, the private prison business wants to make money. They decided that the best way to do that is to "educate" legislators on illegal immigration practices and to write a new law. Do these businesses have too much power?