Gov. Charlie Baker overstepped constitutional separation of powers with his statewide response to the COVID-19 pandemic, a national group alleged in a new lawsuit filed on behalf of Massachusetts small business owners.

The New Civil Liberties Alliance, a non-profit organized to fight what it describes as the "unconstitutional administrative state," filed a case in Worcester Superior Court asking the judiciary to nullify Baker's March 10 state of emergency declaration and the dozens of executive orders he has issued since then.

In its legal filing, the organization argued on behalf of 10 small businesses that the governor was incorrect to adopt emergency powers under the Civil Defense Act because the law is designed for threatening crises such as invasions and natural disasters, not pandemics.

The Public Health Act confers main responsibility for disease control to local boards of health, the NCLA argued, adding that statewide pandemic policies should be in the hands of the Legislature rather than Baker.

"The problem is when you square peg-round hole a civil defense state of emergency into a pandemic, you're not going to effectively treat the underlying problem," NCLA Senior Litigation Counsel Michael DeGrandis told reporters Monday. "You're likely to make it worse because he doesn't have the tools he needs – as in on-the-ground interaction with people in communities, not just in Boston, not just in Pittsfield, but everywhere in between – he just doesn't have that ability."

At a virtual press conference organized alongside the Massachusetts Fiscal Alliance, which is not a party in the case, DeGrandis said NCLA does not question Baker's motives, but wants to "restore constitutional order to government."

"The executive orders are harming countless businesses while infringing on the civil rights of almost everyone in the commonwealth," Fiscal Alliance spokesman Paul Craney said at Monday's event. "The governor's executive orders completely sidestep the rule of law."

While the Legislature has passed numerous new laws in response to the pandemic and its impacts, many of the major rules that are governing life and business activity during the crisis – including mandatory use of face coverings when social distancing is not possible, closure of K-12 schools and child care, and non-essential business shutdowns – have been included in executive orders issued by Baker.

The governor has leaned to some degree on local boards of health during the crisis, delegating enforcement actions and some reporting tasks. He has also enjoyed high approval ratings in public polls during the crisis.

In a MassINC Polling Group survey conducted between May 5 and May 13, 41 percent of respondents Baker's performance managing the outbreak "excellent" and another 35 percent rated it "good." A WGBH/Boston Globe/Suffolk University poll from April 29 to May 2 found 84 percent of those surveyed approve of Baker's approach to the crisis.

The plaintiffs include the business owners in Hubbardston, Lexington, Burlington, and Marlborough, the pastors of churches in Westfield and Medford, and Ben Haskell, headmaster of Trinity Christian Academy in Hyannis.

Plaintiffs said Baker's statewide orders closing non-essential businesses to limit the spread of the highly infectious virus have inflicted enormous economic harm. Several joined Monday's press conference to describe the impacts on their businesses and their frustrations with remaining unable to open their doors to customers.

"I'm tired of waiting," said restaurateur Carla Gomes, who owns Terramia, Antico Forno and Cobblestone in Boston's North End. "We've all just been complacent, but now, we're tired of being complacent. We've lost money, our employees are calling us, they need to get back to work, they're desperate, they don't know what to do. In the restaurant business, you employ a lot of people, and they're all suffering."

The state's unemployment rate surged to a record 15.1 percent in April, reflecting layoffs stemming from the widespread business closures.

Massachusetts is in the first phase of a gradual reopening phase the Baker administration outlined, but it remains unclear exactly when the next phases will begin. Baker plans to announce Saturday when the second phase, which will allow restaurants to host outdoor dining, can start.

Robert Walker, who runs the Apex Entertainment center in Marlborough, said the pain his business has endured "does not end the day the governor decides to let us open up again."

"If we're able to open next Monday, our clients aren't going to be there next Monday," he said. "They're going to be there in three or four months because if you had a wedding or graduation or a business event, you have to go organize that again. So even if we started the race next Monday, our business itself is weeks and months away from booking its first event."

Officials have also warned that they could reintroduce restrictions if public health metrics indicate a rebound in cases of the virus that has killed more than 6,800 residents.

"COVID-19 is a very serious health problem, and I'm sure the governor is doing his absolute best to try to protect the lives of the people in Massachusetts," DeGrandis said. "But it's not his job, it's the legislators' job, and the Legislature has already spoken with the Public Health Act, too."

"We hope to force them to do their jobs," he added.

Baker has repeatedly thanked residents and businesses for the sacrifices they've made to help slow the virus spread, and said he wants to bring business activity back but only when he believes it's safe to do so.

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