Probably not the P.C. answer but....when I took the test(yes, it requires a civil service exam) years ago and did very well and asked why I was hearing no response....was told unless I "was a female minority with connections you can forget it" was the answer I got when I pursued it. I believe they are basically State Police Officers with more of a biological/environmental background. Having some secondary education in those fields may carry more weight(and help you on the exam) than a Criminal Justice degree.
Mass. Env. Police:
http://www.mass.gov/dfwele/dle/
Human Resources exam list:
http://www.mass.gov/?pageID=hrdsubto...edule&sid=Ehrd