In a high-profile case that rocked the commercial shipping industry, a sailor accused of raping a student from the US Merchant Marine Academy has agreed to surrender his credential to work on ships, but he will not be criminally prosecuted.

Longtime merchant mariner Edgar Sison voluntarily surrendered his government-issued credential last week after the US Coast Guard amended an administrative complaint filed against him and charged him with sexually assaulting his subordinate, Hope Hicks, according to Coast Guard documents. Federal prosecutors had recently notified Hicks that that they wouldn't be filing criminal charges against Sison, according to her attorney Ryan Melogy. The Department of Justice declined to comment on the agency's decision not to prosecute Sison.

The two developments effectively resolve a case that prompted reforms in the shipping industry and sparked congressional outrage.

The case attracted national attention nearly two years ago when Hicks posted her account of the incident on a blog followed by mariners under the anonymous moniker "Midshipman X." She said she was on a commercial ship in the middle of the ocean as part of a school training program when one night Sison and other top officers forced her to take shot after shot of alcohol. After she became incapacitated, she said, Sison attacked her. She was 19 years old at the time.

Sison, who did not respond to a request for comment, previously told CNN that he denied Hicks' allegations. By surrendering his ability to work on commercial ships, Sison avoided a hearing on the administrative assault charges against him.

Hick's allegations exposed long simmering problems of sexual assaults in the maritime industry, particularly against students from the Merchant Marine Academy who are sent to sea for months at a time in a mandatory training program. It also revealed the problems and limitations that the US Coast Guard has in investigating such offenses, as a CNN investigation found earlier this year.

Records obtained by CNN showed that the Coast Guard—the main agency responsible for investigating alleged crimes involving those working aboard commercial ships—has long been lenient and inconsistent with sanctions for mariners found to have committed sexual offenses, especially when compared to outcomes in other cases such as drug use. And even when sanctions do occur, CNN found that the agency has done little to keep alleged predators off of ships as investigations stretch on for months or even years.

The Coast Guard, for example, had not taken any disciplinary action against Sison and had even renewed his government-issued credential prior to CNN's investigation. The day after CNN's piece ran in March 2023, the Coast Guard filed a complaint seeking to temporarily remove Sison's credential for an alcohol-related violation, more than a year after Hicks first reported her allegations to the Coast Guard in the fall of 2021. But even then, Sison had still been able to keep his credential while fighting that charge. It ultimately took the agency nearly two years to successfully keep Sison from working on commercial ships.

This week, the Coast Guard told CNN that it "is committed to preventing sexual misconduct in the maritime industry and responding to allegations in a timely, professional, and consistent manner."

In a statement to CNN, Hicks said she was disappointed Sison wasn't criminally charged, but she expressed relief that her long journey had come to an end. "I hope this will show others in similar situations that justice is possible, and that more survivors will achieve similar outcomes."

Do you have a tip about the US Coast Guard or sexual assault at sea? Email melanie.hicken@cnn.com.