BOSTON -- The state’s highest court will hear arguments Friday in a lawsuit challenging Gov. Charlie Baker’s authority to declare a COVID-19 state of emergency, a directive that allowed him to unilaterally shut down churches, schools and businesses to prevent spread of the coronavirus.

The lawsuit, filed by a coalition of small business owners and church pastors calling themselves the New Civil Liberties Alliance, argues that Baker didn’t have the powers under the state’s Civil Defense Act to declare an emergency.

“The Civil Defense Act is a 1950s-era statute designed to protect the commonwealth from foreign invasions, armed insurrections and civil unrest associated with natural disasters,” the coalition wrote in the suit. “It has never before been invoked for a health emergency.”

The coalition claims Baker overstepped his authority by issuing a litany of other executive orders based on the emergency declared on March 10.

“Gov. Baker’s decrees have extended COVID-19’s misery to virtually everyone, including the healthy, by unnecessarily creating social, economic, educational and spiritual crises on top of the health crisis,” they wrote in a recent filing.

Assistant Attorney General Douglas Martland, who is defending the Baker administration, says the emergency orders pass constitutional muster because they are “content neutral, narrowly tailored to serve a substantial governmental interest, and allow for other opportunities for expression.”

“Because COVID-19 is spread mainly by person-to-person contact, and because large in-person gatherings can significantly contribute to community spread, the orders limit people’s ability to assemble in person,” he wrote. “None of those distinctions or exclusions is dependent on anyone’s political, religious or ideological beliefs.”

Under his emergency declaration, Baker has wielded sweeping powers to direct the state government’s response to the pandemic. Since the outbreak began in mid-March, he has issued more than three dozen orders — from those closing schools, day-care centers and other businesses to a stay-at-home advisory and limits on public gatherings — to prevent the spread of the virus. Many of the orders remain in effect, with no expiration date.

The directives handed down by the governor function essentially as temporary laws, bypassing the Legislature’s traditional role in the policymaking process.

In court filings, Martland pointed out that legislative leaders have done little to oppose Baker’s orders in court filings, challenging claims by the plaintiffs that the emergency orders bypassed the Legislature.

“Since the governor’s emergency declaration, the Legislature has enacted a host of laws that approvingly acknowledge the state of emergency and are even contingent on the existence of a declared emergency,” he wrote.

The Massachusetts Medical Society, Health & Hospital Association and other medical groups have come to Baker’s defense, arguing in a legal brief that if the coalition succeeds in stripping the governor of his authority to impose emergency orders, “people will needlessly die” if there’s a second wave of virus infections.

“The crisis is hardly over ... and the unhappy recent experiences of other states and countries should remind us that resurgences are not just possible but likely,” the groups wrote. “The governor’s emergency powers have helped to keep Massachusetts on a healthy path, and if the court abrogates that authority we fear the consequences will be severe.”

Christian M. Wade covers the Massachusetts Statehouse for North of Boston Media Group’s newspapers and websites. Email him at cwade@cnhi.com

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