The Trump administration's decision to withdraw the US from the UN climate treaty may be illegal, according to some experts. The move, announced in a presidential memorandum, marks the first time any country has exited the agreement. The UN climate body requires a one-year notice for withdrawal, and the US will remain a party for that duration. However, the memo does not specify whether the administration will submit a formal notice of termination to the UN.
Harold Hongju Koh, former head lawyer for the US State Department, believes the president lacks the authority to make such a move. Michael Gerrard, a climate law expert, notes that the US entered the UNFCCC with Senate consultation and approval, raising questions about the president's unilateral exit. The UNFCCC and the Paris climate agreement both require a one-year written notice for withdrawal, but the Paris agreement was never ratified by the US Senate.
Some scholars argue that the president can unilaterally end treaties, either legally or practically, as Congress has acquiesced to the executive branch in the past. Curtis Bradley, a University of Chicago law professor, supports this view. However, Koh suggests a "mirror principle" should apply, requiring the same congressional input needed for entry to withdraw. This principle is not explicitly stated in the US Constitution, and the Supreme Court has never ruled on the topic.
The withdrawal has sparked controversy, with Rhode Island Senator Sheldon Whitehouse calling it illegal and corrupt. Melinda St Louis, director of Public Citizen's Global Trade Watch, criticizes Trump's contempt for international efforts, which she believes will damage the nation's credibility and harm future generations. The timing of the withdrawal, on the anniversary of devastating fires in Los Angeles, has also raised concerns about the administration's commitment to climate action.
Experts disagree on the process for re-entering the UNFCCC. Some believe a new approval from the Senate is required, while others argue that the 1992 Senate vote remains valid. Sue Biniaz, former principal deputy special envoy for climate, suggests the US could rejoin the UNFCCC based on the 1992 approval, but the political climate may make this challenging.
