Former national security adviser John Bolton could be the firsthand witness the Democrats need, according to the New York Times. This qualifier makes Bolton’s testimony relevant to the Senate’s impeachment trial. But in terms of impact, this changes very little.

The New York Times alleges that in Bolton’s new memoir, he says Trump directly tied the Ukrainian military aid freeze to an impending investigation into the Bidens. If this is true, Bolton could be the missing link between the two established facts in the case against Trump. The first fact is that more than $391 million in security assistance to Ukraine was withheld and later released. The White House has denied that the freeze had anything to do with the second fact — that Trump wanted and expected Ukraine to investigate 2016 election meddling and Ukrainian energy company Burisma Holdings.