Me and my boyfriend have been together for a year and we would like to get married but he is illegal and came into american without a visa.he has been arrested for driving wihtout a licenes and that's all.he pays taxes. Can we get married and then apply for his papers?we are expecting a child as well:)

It depends on exactly how he entered the US and whether he is grandfathered for INA section 245(I). If he entered without inspection (EWI), he needs to be able to use 245(I) to waive that immigration violation to get his PR here in the US. If not, he needs to apply for an immigrant visa at his home consulate along with a waiver for the immigration violation. The waiver will be based on hardship to the USC spouse and child. The hardship is not based on separation or money.

Difficult case, will be very fact-specific. Consult with an experienced immigration attorney.