As has been mentioned, your thesis statement must summarize your purpose in writing the paper. It should tell the reader what you plan to prove to them.
I do not know if YOU personally favor a lifetime license suspension for 1st time offenders or not, but THIS MUST BE CLEAR in your paper.
If YOU do, one of your arguments could be... 'Suspended License or Ended Life?'
If you investigate the laws of your local county and state, they can be used as a arguing point for your view as well.
It goes like this:
Introduction: Tell them what you are going to tell them (briefly) using a thesis sentence.
[In this paper I will describe why a person should have their license suspended for DUI after the first/second offense.]
Body: Tell them what you just told them (in detail using specific arguments).
Conclusion: Tell them what you told them in a summary without using new information.
Heres some websites that may give you some more argument material based on current laws and their reasons in different states. (If the links don't work, just type the address into your browser.)
Good luck on your paper.