While the authors of the newly released Senate immigration bill touted its multibillion dollar investment in border security, critics are seizing on what they describe as a major loophole -- giving the government "discretion" to choose when to enforce immigration laws. 

The union representing Immigration and Customs Enforcement agents has long complained that the Obama administration has made their job harder by preventing agents from detaining and deporting select illegal immigrants. They had petitioned members of the so-called "Gang of Eight" -- the lawmakers writing the immigration bill -- to address those concerns in the package. 

Read more from Fox News