It’s August. Why are Mass. legislators done for the year?

Massachusetts lawmakers have gone home for the year.EPA

The Massachusetts legislative session wrapped up for 2014 this week, which might leave some wondering: is it December already? How can they be done for the year if the leaves are still on the trees?

There are some good reasons for lawmakers to give themselves a firm end date. It encourages them to finalize bills they’ve been working on all session, and it ensures that soon-to-be elected House and Senate members get a fresh start come January.

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But in order to really understand why legislators get to go home early we have to cross state borders and travel back in time to the colonial period.

So, what is a legislative session?

A legislative session is the period during which legislators get together to vote on legislation. No session, no votes. That doesn’t mean that when the session ends, legislators go off on vacation. They can still participate in committee meetings, plan future activities, and research key issues. If something urgent comes up, they can even be called back to the statehouse for an emergency session.

Massachusetts holds one session every year, beginning in early January. In odd years, when there’s no election, the session runs through mid-November. In election years, like this one, it ends on July 31 — which gives members extra time for electioneering.

While other states have experimented with various legislative calendars, Massachusetts has had regular, annual legislative sessions since the beginning — even before it was a state. And whereas many other states place constitutional limits on how long sessions can last, in Massachusetts the legislature gets to decide when to adjourn. If they wanted, lawmakers could change the end date.

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How does it work in other states?

It varies quite a bit. Relatively speaking, Massachusetts’ sessions are quite long, lasting over 300 days in odd years and over 200 in election years. In Colorado, a session lasts 120 days. In Florida, it’s 60. The Connecticut legislature adjourns in time for summer, and New Hampshire winnows its calendar to 45 working days. There are even four states that don’t hold annual sessions but convene instead every other year: Montana, Nevada, North Dakota and Texas.

The National Conference of State Legislatures keeps a comprehensive list.

Why don’t sessions last the whole year?

In the early days of the nation, being a state legislator wasn’t a full-time job. When you weren’t crafting laws for your state, you might be a silversmith or a farmer. So the earliest legislative sessions had to be short, in order to let people get back to their livelihoods. And because our economy was largely agrarian, legislative sessions tended to meet in winter, at the low ebb of the farming cycle.

During the 19th century, concern grew that even these part-time legislatures had become too powerful. In response, states imposed a series of limitations on how long legislative sessions could last, and a great many states actually switched from annual sessions to biannual ones (meaning every other year.) For a while Alabama even had a quadrennial legislature, meaning it met only once every four years.

In the 20th century, the pendulum swung back the other way. Not only did most states return to annual sessions, but some made a push for truly “professional” legislatures, with full-time members and full-time salaries to match.

Massachusetts is one of the states that has tried to “professionalize.” Today, Massachusetts legislators earn roughly $60,000 in salary, which is just below the state’s median wage. While a $60,000 salary is substantially lower than the $90,000 earned by California representatives, it’s well above the $28,000 earned in Connecticut, the $15,000 in Rhode Island, or the $100 in New Hampshire.

Do we really need a full-time, professional legislature?

The answer to this question will depend on your politics. Part-time legislatures with severely limited sessions are likely to pass fewer laws, which is good news if you’re a fan of small government. Not surprisingly, traditionally conservative states and southern states tend to have the most austere restrictions.

By contrast, more progressive states like Massachusetts, California and New York have moved to lengthen legislative sessions and increase pay, as part of their effort to make state government more competent and more effective. If anything, this imperative has gotten more pressing, as congressional gridlock kicks more and more issues down to the states.

Do we even need sessions at all?

Leaving aside the question of whether an annual session should end in July (or indeed May), it can make sense to organize state government according to sessions.

• New legislators, new session. Come January, Massachusetts will have a whole new class of representatives, and it makes sense to somehow mark that transition. Opening a new legislative session effectively does that. It resets all legislative activity so that the new cohort can address problems in their own way.

• Deadlines are powerful. Just as a firm deadline has a way of focusing attention, the session end date can be a powerful motivator. Knowing that you need to pass a bill by a certain date — or start over some months later — can help build consensus and support compromise.

Even these may not be good enough reasons to set aside certain times of the year for law-making. At the federal level, the notion of a time-bound legislative session is slowly dissolving. Now, even when the Senate is in recess, some Senators hang around to hold “pro forma” sessions. Not much gets done in these “pro forma” sessions, but they keep the president from making recess appointments.

Here in Massachusetts, though, there’s one overriding reason that our legislative session ends this week. It’s an election year. Which means that for the next few months, state politicians won’t be voting for laws, they’ll be trying to earn people’s votes so they can come back for another session.