Lionel Saxon is a U.S. Navy Lieutenant Commander who appeared in Dressed to Kill (episode).
After Michael Walden Elliot became paranoid that someone was likely going to kill him for information that he uncovered, he called Lt. Commander Saxon to meet in private at a hotel to disclose information relating to the closing of shipyards near Macao. He then agreed to meet, also making clear that he'll be wearing a naval officer's uniform to indicate who he is. Unfortunately, before he could arrive at the hotel to meet with Elliot, the disgraced private investigator Nicholas Bodeen, who had wiretapped their phone calls, had beaten him to the hotel and shot the Senate aide with a gunshot after posing as the Lieutenant Commander, to ensure that the shipyards weren't closed down due to a casino there owned by Ling.
He was later brought into questioning about his knowledge about Elliot by NCIS, due to the MRCT member Anthony DiNozzo killing Bodeen in self-defense. Before leaving upon telling them everything he knew, he asked Gibbs whether Bodeen had been trying to pose as him.