There were two components to last week's shelter-in-place request in Watertown, Massachusetts. The first was a request that people not to leave home. The second was a door-to-door search by heavily armed law enforcement officials. Those are two very different things, with different implications. But neither was illegal.

No one in Watertown had to stay at home. The shelter-in-place was optional, largely an effort to ensure public safety in the classic sense of such requests. Time explains the difference:

“The lockdown is really voluntary, to be honest with you,” says Scott Silliman, emeritus director of the Center on Law, Ethics and National Security at Duke Law School. “The governor said he wants to use sheltering in place. Sheltering in place is a practice normally used if you’re dealing with a pandemic, where you’re telling people, ‘You may have been exposed and we want you to stay exactly where you are so we can isolate everything and we’ll come to you.’”

The “shelter in place” request is legally different from a state of emergency, which Patrick declared earlier this year as winter storm Nemo descended on the Bay State.

The ACLU agreed. In a phone interview Monday, Carol Rose, executive director of the ACLU of Massachusetts, told The Atlantic Wire that her organization was in contact with attorneys for the city, state, and the Department of Homeland Security on Friday. While the organization was concerned about how open-ended the request seemed to be, it was assured that the order was voluntary and that no one would be arrested if he or she left home in the midst of it. It would have been hard for the police to crack down anyway, given that various Dunkin Donuts locations were allowed to remain open.

But the image of a family sitting around a table, nervously riding out the order by playing board games, is very different than the one presented by the searches.

Under the Fourth Amendment, homeowners have the right to refuse a request for a search if the police don't have a warrant. But that rule has an exception. If there are exigent circumstances, like the threat of imminent danger, a warrant isn't necessarily needed, but the police must still have probable cause.

It seems unlikely that many residents of Watertown felt like exploring that particular legal nuance by refusing the police entry. Nor is it not clear if any did; a spokesman for the Watertown police department didn't answer a question to that effect. It is clear that doing so would have required a great deal of courage. The conservative blog Poor Richard's News transcribes a YouTube video that has since been removed.

The gentleman here (if you can call him that) notes that both times his house was searched the law enforcement officers “asked” permission to do so, but he didn’t feel like he had much of a choice as the police team had guns pointed at his face. On the one hand, he expresses relief that the terrorist was caught and that he’s still alive, but he seems to struggle with questions about whether the police action was appropriate.

The ACLU would like to hear from the person in that video. Rose said that the organization had received a number of concerned comments from people about the searches that took place, including some from residents of Watertown. None, however, from people whose homes had been searched. (The Watertown police spokesperson, Michael Lawn, wasn't able to say how many homes had been searched, saying only it was "a lot." When asked if that was because the FBI was leading on the effort, Lawn indicated that it was just because it was "hard to tell.") 

Calling the searches "a fourth amendment question that wouldn't change whether or not the shelter-in-place" was in effect, Rose explained that the organization's hands were tied. "We're concerned about any precedent that this might set," Rose said. "and are interested in hearing from people whose rights may have been violated."

The day's searches were themselves not without precedent. Following the Atlanta Olympic bombing in 1998, authorities searched the woods of North Carolina. Earlier this year, cabins near Big Bear Lake, California, were searched in the hunt for Christopher Dorner. Neither of those incidents involved as many homes or as much media attention, nor did either occur in heavily populated residential communities. And, as with Friday's hunt, they were likely perfectly legal.

"Courts look at it differently when there's a threat of public safety than if the police just want to search," the ACLU's Rose pointed out. She noted a situation several years ago in which the Boston police wanted to conduct door-to-door searches seeking out illegal firearms. In that case, the ACLU spoke out against the proposal, and it was dropped.

The images from Watertown were scenes from a movie brought to life. Heavily armed and armored law enforcement officials knocking on doors with rifle-toting backup. But there's no reason to assume it was an infringement of civil liberties. "We're trying to get facts on the ground of what really happened," Rose said. Unless they do, what happened in Watertown was just an extreme example of law enforcement at work.