The makeup of the 113th Congress contains only one member who considers their religious affiliation "unaffiliated", that is 0.2%. To put this into perspective as to why it is an issue look here
http://www.pewforum.org/files/2013/01/congress-1.png
As you can see, for every other background the population versus the representation in government is much more proportionate but in regards to the non-religious 20% of adults identify as "Unaffiliated" and only 0.2% of congress identify that way. This is much more disproportionate than any other background and this proves that the non-religious are oppressed in this country which is a violation of the 14th amendment which guarantees equal protection under the law, but without representation we are inadvertently oppressed by law.