“We should all agree that in our constitutional democracy, the executive’s ability to attack another country is constrained by the law,” Justin Florence, the group’s legal director and a former Obama White House lawyer, wrote in an essay announcing the lawsuit. He added: “Some countries may tolerate a head of state launching a new conflict without offering a clear legal justification, but we should not.”
In a letter to Congress, Mr. Trump asserted, with little detail, that his constitutional powers as commander-in-chief gave him sufficient basis to unilaterally launch the attack to advance American interests, including deterring further use of chemical weapons.
Many presidents of both parties have claimed a right in domestic law to make unilateral use of limited force abroad to advance Americans interests. For example, former President Barack Obama did so in 2011, when he directed the American military to take part in the NATO intervention in Libya without congressional authorization.
Still, the Obama administration released a memorandum from the Justice Department’s Office of Legal Counsel laying out a rationale for why the American interests at stake in Libya were sufficient to justify his move.
Shortly after the Syria strike last month, the Trump administration distributed unsigned talking points among representatives in various agencies about the strike’s legal basis. They were never formally made public, but Martin Lederman, a former Justice Department lawyer in the Obama administration, obtained a copy and published them on the Just Security blog. An administration official later confirmed their authenticity.
“This domestic law basis is very similar to the authority for the use force in Libya in 2011, as set forth in an April 2011 opinion by the Department of Justice’s Office of Legal Counsel,” the unused Trump talking points said.
However, as Mr. Lederman pointed out, the 2011 rationale relied in part on the need to bolster the credibility of the United Nations Security Council, which had authorized nations to use force to protect Libyan civilians. By contrast, the Security Council did not authorize a strike to punish Syria’s use of chemical weapons, so the Syrian intervention undermined the United Nations system for constraining war, he said.
The United Nations Charter, a treaty the United States ratified, recognizes only two legal ways for a country to use force on another soil without its consent: if the Security Council has authorized an attack, or in self-defense. The Trump talking points memo had a section labeled “international,” but it consisted of policy arguments, not legal ones, and did not mention the United Nations Charter.
There are some precedents. The United States bypassed the United Nations system in 1999, when the Clinton administration directed the military to participate in the NATO intervention in Kosovo. Still, that administration put forward something of a public legal rationale, citing a list of factors that it argued made the operation legitimate.
The Obama administration considered attacking Syria in 2013 for using chemical weapons, too, and during preliminary deliberations Mr. Obama’s legal team developed an argument that was similar to the Kosovo precedent. But in the end, in part because that international law argument was so thin — unlike Kosovo, not even the multilateral NATO alliance was going to be involved — Mr. Obama pulled back and asked Congress for authorization. The crisis was then resolved in a different way and no strikes were conducted.
Late last month, two Democrats in Congress — Representative Adam Schiff of California and Senator Tim Kaine of Virginia — sent a letter to Mr. Trump urging him to explain the legal basis for the strike. But the administration has not responded, aides said.
Now, Protect Democracy is hoping to shed some light with a lawsuit that, at the least, might identify whether legal memos exist, whether or not they are made public.
Mr. Florence wrote that the Trump administration’s silence suggests one of two “disturbing” possibilities: Either it is trying “to prevent informed debate and oversight of the president’s ability to take the country into a new armed conflict with another country,” or it “never rigorously made an assessment about the legality of the Syria strikes” in the first place.