Massachusetts has an incarceration rate that is well below the national average - in fact, if you live in Massachusetts you are only half as likely to go to county jail than the average American.

Incarceration by demographics
Like most states, only about 6% of inmates are females. The most common types of crimes committed in Massachusetts are property crimes, theft/larceny and drug-related crimes. Marijuana is not legal in this state but there is a special law that treats a first time possession offense similar to a minor traffic offense.

DUI's also account for a large percentage of arrests in Massachusetts. You can be charged with DUI either under per se laws or impairment. Per se laws are more common because they only stipulate that if your BAC is above 0.08% you are considered drunk, regardless of impairment. This is easier to test for and convict whereas impairment alone can be subjective.

How do you end up in a Massachusetts County Jail?
Usually you end up in county jail as a result of a misdemeanor charge. You can also be sentenced to a county jail for a felony, though you are also a candidate for prison at this point. County jails typically house inmates who are serving a year or less while you may spend several years (or even life) in prison.

What you see on television and the movies is usually prison - there is a lot more violence because people have longer sentences (they have less incentive to obey the rules since release times are pretty much fixed).