[...] The coordination between the Trump Tower visitor and the Russian prosecutor general undercuts Ms. Veselnitskaya’s account that she was a purely independent actor when she sat down with Donald Trump Jr., Jared Kushner, the president’s son-in-law, and Paul J. Manafort, then the Trump campaign chairman. It also suggests that emails from an intermediary to the younger Mr. Trump promising that Ms. Veselnitskaya would arrive with information from Russian prosecutors were rooted at least partly in fact — not mere “puffery,” as the president’s son later said.

In the past week, Ms. Veselnitskaya’s allegations — that major Democratic donors were guilty of financial fraud and tax evasion — have been embraced at the highest levels of the Russian government. President Vladimir V. Putin of Russia repeated her charges at length last week at an annual conference of Western academics. A state-run television network recently made them the subject of two special reports, featuring interviews with Ms. Veselnitskaya and Mr. Chaika. The matching messages point to a synchronized information campaign [....]