A group of part-time community college instructors filed a lawsuit against the commonwealth of Massachusetts, saying that hundreds of adjunct faculty in the state's public higher education system are unfairly denied healthcare coverage. The lawsuit, filed in Suffolk Superior Court on behalf of five instructors, follows nearly a decade of unsuccessful wrangling with state legislators to get an adjunct health insurance bill enacted into law. It also comes as schools, particularly community colleges, are increasingly turning to adjuncts amid burgeoning enrollment.