Washington (CNN) Rep. Tulsi Gabbard did not meet the threshold to speak at Friday's Iowa Democratic Party Liberty and Justice Celebration, which is expected to be attended by 14 other Democratic presidential candidates.

To qualify for the event, candidates could either open at least two field offices in the state with at least 10 dedicated field organizing staff or buy the Iowa Democratic Party's voter file, according to Jonah Hermann, the spokesman for the state Democratic Party. A voter file is a digital database of official, publicly available government records of who is registered to vote and who voted in past elections.

"To our knowledge," Hermann said, "the congresswoman did neither of those things."

CNN has reached out to the Gabbard campaign for comment.

The event in Des Moines is described as the "premier event of the caucus season" by the Iowa Democratic Party. Iowa is a key early-voting state, and its first-in-the-nation caucuses will take place on February 3.

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