U.S. Bankruptcy Judge Robert Faris found that Mesa Air Group used the confidential information to "gain a competitive advantage ... to enter the market for Hawai'i interisland air transportation services."

Hawaiian sued Phoenix-based Mesa last year for $173 million in damages, alleging that Mesa used confidential financial data from Hawaiian to set up go! airline.

Mark Dunkerley, Hawaiian's president and chief executive officer, applauded the decision.

"Today's ruling is a triumph for fair competition and ethics over dishonesty and illegal behavior. Nobody benefits when a company like Mesa misuses confidential information to gain an unfair competitive advantage, then lies about it and destroys evidence," he said.

Dunkerley said evidence presented at trial confirmed Hawaiian's contention that Mesa's strategy was to reduce competition in the marketplace.

"Mesa pretends that they are in Hawaii to help the consumer. As the evidence in this trial showed, the reality is that Mesa's intent was to drive local competition out of business and raise fares. We are pleased that the Court laid out the facts for all to see."

In his ruling, Faris rejected a request by Hawaiian Airlines to bar go! from selling tickets for interisland service for one year.

"In this case, the award of money damages adequately redresses the harm suffered by HA as a result of Mesa's breach of the confidentiality agreement," Faris wrote.