Sen. Susan Collins declined President Trump’s invitation to go to the White House for the announcement of his pick to fill the Supreme Court seat of retiring Associate Justice Anthony Kennedy on Monday night.

“She appreciates the invitation, but will not be attending,” Collins spokeswoman Annie Clarke said.

Collins is a critical swing vote in the Senate confirmation process for whomever Trump nominates to replace Kennedy.

Trump introduced Brett Kavanaugh as his nominee to replace Kennedy during the event. It marked the second time Trump has moved filled a vacancy on the high court. Trump selected Neil Gorsuch in January 2017 to fill the seat left vacant after Justice Antonin Scalia died in February 2016.

The Senate confirmed Gorsuch in April 2017.