You must pay your taxes if you work in the US. Although the details of immigration reform are uncertain, like I mentioned in my first post on this topic, the proposals that have been released so far all mention filing tax returns. The US taxes people on earnings from work preformed in the US. The taxes that you pay will go towards government services.

Here are some helpful tips to help you start preparing now:

You must file both a state and federal tax return in most states, even if you did not have legal permission to work. The tax return allows the government to decide how much you might owe in taxes or whether you qualify for a refund.
You can file without a valid social security number. You just need to apply for an individual taxpayer identification number (ITIN). The ITIN allows you to file your tax returns by placing that number on the form instead of a social security number.
You can apply for an ITIN with the Internal Revenue Service (IRS), at www.irs.gov/, or by calling 1-800-829-1040. Filing tax returns can help later on when you apply for lawful immigration status. If you were required to file, but never did so it could have immigration consequences.

Taxes play an important role in immigration, and nonpayment of taxes can create an issue of moral character that can affect your future citizenship application and have other immigration consequences.