IN ORDERING THE SHUTDOWN of large swaths of the state’s economy, Gov. Charlie Baker is relying on a 70-year-old state law that was clearly not written with the coronavirus in mind.

The Civil Defense Act of 1950 was passed at the beginning of the Cold War, a time when the United States was increasingly worried about the spread of communism and military threats from the Soviet Union. The law allows the governor to declare a state of emergency when the state is threatened by enemy attack, sabotage, riots, fires, floods, earthquakes, droughts, or “other natural causes.”

Presumably COVID-19 would fall in the category of natural causes. It’s a good example of how the language contained in the law does not quite fit today’s circumstances. Baker finds himself shoehorning 2020 concerns about social distancing, contact tracers, and non-essential businesses into a 1950 law preoccupied with military threats and nuclear fallout shelters.

There have been legal challenges to orders issued by governors in California, Michigan, Maine and a handful of other states. But only one lawsuit has been successful – in Wisconsin, where the state supreme court sided with Republican lawmakers who challenged an extension of the governor’s stay-at-home order. “An agency cannot confer on itself the power to dictate the lives of law-abiding individuals as comprehensively as the order does without reaching beyond the executive branch’s authority,” the court ruled.

Here in Massachusetts, there have been challenges to the governor’s authority on constitutional grounds (gun sales) and fairness (recreational marijuana), but neither case questioned the governor’s ability to declare a state of emergency and order sweeping changes to society.

Baker has been asked about his legal authority a couple of times. Once he didn’t answer the question directly. On a second occasion, he was asked if he expected to be sued over his four-phase reopening plan. “We’ll see,” he said.

A request to talk to one of his legal advisors was turned aside. Instead, the governor’s spokeswoman issued a statement saying his emergency declaration was issued to protect the state’s citizens. The statement also pointed to the sections of the law cited in the declaration itself and his many executive orders.

According to the state website, all but one of the previous state of emergency declarations in Massachusetts dealt with storms. The exception was a state of emergency declared by Baker to address the Merrimack Valley gas explosions in 2018.

“Declaring a state of emergency helps state agencies protect you from the immediate dangers of a disaster, in part by providing resources for rescue, shelter, or evacuation. The instructions you receive during a state of emergency will depend on the emergency itself — every situation is different, and different factors will impact the decisions made by state officials,” according to the state website.

In declaring a state of emergency on March 10, Baker relied on sections 5, 6, 7, 8, and 8A of the Civil Defense Act. In broad terms, the sections grant the governor authority to seize personal and real property (and pay the owner reasonable compensation), to work jointly with the federal government and other states, to exercise a wide assortment of other powers, to issue executive orders that have the force of law, and to have those orders take precedence if they conflict with any existing laws.

In an order shutting down much of the state’s economy and limiting gatherings of people to stop the spread of the coronavirus, Baker cited only three of the five sections and nearly all of the wording was drawn from section 7 dealing with the wide assortment of powers he can wield.

The order said the three sections of the Civil Defense Act authorize the governor “to exercise any and all authority over persons and property necessary or expedient for meeting a state of emergency, including but not limited to authority over assemblages in order to protect the health and safety of persons, transportation and travel by any means or mode, regulating the sale of articles of food and household articles, and policing, protection, and preservation of public and private property.”

The wording of the governor’s order mashes together a number of sections of the law together, so it’s helpful to analyze it phrase by phrase.

The first phrase about exercising “authority over persons and property necessary or expedient for meeting a state of emergency” is excerpted from section 7 of the statute. But in the law that phrase is qualified. The law says the governor has authority over persons and property, “which the general court in the exercise of its constitutional authority may confer upon him as military forces thereof, and specifically, but without limiting the generality of the foregoing, the governor shall have and may exercise such authority relative to” a number of specific powers listed in the statute.

It’s unclear what the reference to military forces means, but the language seems to imply that the Legislature “the general court” is a carryover from the colonial era has some role to play in regard to powers exercised by the governor.

The rest of the governor’s order refers to some of the specific powers the governor can wield during an emergency. Baker’s order cites four of them, and does some selective editing of the statute in summing them up.

For example, the governor’s order says he has “authority over assemblages in order to protect the health and safety of persons.” The actual language of the statute says he has authority over “assemblages, parades or pedestrian travel in order to protect the physical safety of persons or property.”  The word “health,” which is contained in the governor’s order, does not appear in that section of the statute and the governor’s order omits the reference to “physical” safety contained in the statute.

The governor’s order says he has authority over “transportation and travel by any means or mode.” That is not the exact language of the statute, but it’s a fair summing up. The statute refers to “transportation or travel on Sundays or weekdays by aircraft, watercraft, vehicle or otherwise.”

The order says the governor can regulate the sale of articles of food and household articles, wording that is drawn directly from the statute and would seem to give him the authority to shut down or regulate the operation of restaurants, stores, and supermarkets.

The order quotes the statute directly in saying the governor has authority over “policing, protection, and preservation of public and private property,” but the meaning of that phrase is far from clear in the context of a shutdown of many of the state’s businesses to stop the spread of the coronavirus.