INS does not...does not accept common law marriages because here it is a state by state law not a federal law for common law marriages. They require a means of support for the immigrant. As part of the immigrant agreement the immigrant swears to not accepting or applying for public assistance i.e. welfare and such so there needs to be a person that is responsible. That is why they look at parent's and spouses because they can take those people and sponsors to court if they fail in their sponsorship roles of ensuring that the immigrant does not end up a burden on the society. It doesn't keep it from happening but it does work for the first two to five years of the probational green card. So you say how do I know this? Well, my now x-husband is back in Oz with his Mummy and I am still here in USA and I had to go through this process when we were married. He did get his green (pink) card, but it was a year for the application process and then the two years of probational card before they issue the second five year card wich is still somewhat probational. At the end of 5 years with that card the immigrant then gets the permanent card which then at the end of that 5 years is then eligible for citizenship. Even being here in the USA and living here it took a year and it was nearly $2500.00 to get to the five year provisional card.