Obama Choosing not to Enforce Laws

I am currently working on sending one of my more liberal friends a list of times in which Obama has chosen not to enforce laws. The reason for this is to support the idea that Obama had a choice in allowing funding for Texas’ Women’s Health program to be pulled. If you have any advice and/or references that I can use in compiling this list, I would be very grateful. Of course, I will be doing the bulk of the research myself, but these instances are so numerous I may not be aware of them all.