Many incoming law students profess a desire to practice public interest law upon graduation. For whatever reason, a humongous percentage of these end up employed in the private sector. Perhaps some had a legitimate change of heart. A lucky few voluntarily chose a prestigious firm with a lucrative salary.
Others never intended to work in the public interest, but only expressed that desire in an attempt to appear attractive to admissions committees. But all too many were forced into an unwanted career due to the restrictions imposed by their student loan repayment obligations.
Here are some loan repayment assistance programs for lawyers http://www.top-law-schools.com/tls-guide-to-lrap.html