Gordon Sondland United States Ambassador to the European Union arrived to Kyiv

On a warm afternoon in July Gordon Sondland arrived at Kyiv's swanky Hyatt Regency Hotel its 21st-century glass facade reflecting the 1,000-year-old St. Sophia's Cathedral.

Despite a dramatic opening week of public testimony on Capitol Hill, the House impeachment inquiry till now has been short on mystery or suspense. While witnesses last week painted a damning portrait of a president willing to abuse his office to secure investigations of his political rivals from a dependent foreign power, there were relatively few new revelations, and their stories were consistent with each other.

About a half-hour late for his interview, he was led to a makeshift hotel-room studio set up by state-run Ukrainian broadcaster UATV. Facing him was Kari Odermann, a news anchor for the channel. She led with what at the time was a throwaway question to warm up her guest.

Wednesday’s testimony, however, moves onto unstable ground, which could make it the most important session yet. After a week of testimony from government officials who mainly experienced the Ukraine scandal as a force interfering with their normal foreign policy work, the public is due to hear from Gordon Sondland, the U.S. ambassador to the European Union, who reportedly sits at the center of that interference as one of the alleged principals in a presidential conspiracy to withhold $391 million in authorized security assistance from Ukraine in exchange for investigations of former Vice President Joe Biden and his son Hunter.

"Tell me about how your day was," she asked. "Well, I had a great lunch with my team," Sondland, the U.S. Ambassador to the European Union, replied with a grin. Before that, he added, he had "a wonderful hour-long meeting" with Ukrainian President Volodymyr Zelenskiy, who had spoken to U.S. President Donald Trump a day earlier.

Critically, Sondland had multiple direct conversations with Trump, making him the first witness who could directly implicate the president in bribery. Further, he has changed his story repeatedly as it has proved inconsistent with the testimony of other witnesses.

Four months later, as Sondland prepares to testify publicly on November 20 in the U.S. congressional probe that could lead to Trump's impeachment, he may spend some time thinking about his brief trip to Kyiv and that lunch on the terrace at Sho, the upscale Ukrainian restaurant where he shared a meal and a bottle of wine with State Department staff and then called the president of the United States.

Sondland faces legal peril, as House Democrats have suggested he may have perjured himself, and legal scholars are pointing to the potential that federal bribery statutes have been violated. All of this could motivate the Trump supporter to finally tell the full truth. Alternatively, he could continue to cite a faulty recollection of key events or even plead the Fifth, potentially placing himself in further legal jeopardy.