Bruce Lucier

From Memory Alpha, the free Star Trek reference.

Bruce Lucier was an acquaintance of Julian Bashir.

In 2367, he held a New Year's Eve party at his home which Bashir and his Andorian friend Erib attended. Elizabeth Lense was also present at the gathering. During the party, another guest would point out Erib to Lense and tell her that the Andorian was Bashir. Lense would go on believing Bashir to be an Andorian for the next four years. (DS9: "Explorers")

Lucier was only mentioned on-screen once and never seen, so the nature of his acquaintance with Bashir and Lense is unknown, although it seems likely he was another medical student. Judging by the name, one can also assume he was a Human.