Maria Ressa, the CEO of the news site Rappler and a vocal critic of Philippines President Rodrigo Duterte, spent a night in the custody of the Philippines National Bureau of Investigation last Wednesday after she was arrested in connection with a “cyber libel” charge against her website. “I think it’s definitely intimidation, for me to spend one night in detention,” she told CNN’s Brian Stelter on “Reliable Sources” on Sunday. “I came out of that night thinking this is now a travesty of justice.”The charges stem from an article that was written by Reynaldo Santos Jr. and published in 2012 by Rappler. The piece claimed that the chief justice of the Philippine supreme court was using a car linked to a businessman who had been accused of involvement with illegal drugs and human trafficking. The businessman, Wilfredo Keng, filed the complaint. Ressa, who worked for CNN before she founded Rappler, was arrested the week after she and her website were indicted.On Sunday, Ressa criticized her indictment because it invokes a “cyber libel” law that was enacted two years after the article was published. The NBI originally said Ressa could not be charged, but the country’s Department of Justice overturned that judgment because the news article was updated in February 2014. Her attorneys have said the update was “merely a punctuation change.””They’re applying a law retroactively. It’s unconstitutional,” Ressa said. “And that’s part of what is shocking about all of this.”The indictment is the second time in recent months that the government has brought charges against Ressa. She was indicted last November for tax evasion.Civil liberties advocates claim the country’s actions are an attempt to stifle free speech and criticism of Duterte. Rappler has received accolades from human rights groups and others because of its reporting on Duterte’s brutal war on drugs. Time Magazine included Ressa in its Person of the Year issue that honored journalists who have been targeted for their work.One of Ressa’s lawyers, JJ Disini, told CNN last week that the timing of Ressa’s arrest was “unusual.” She was arrested hours before the deadline to complete bail proceedings, and her lawyers were unable to post bail in time to avoid detention. “The government seemed bent on making sure I spent the night and was processed as a criminal,” Ressa said Sunday. “Again, if they think that will scare me, all that does is, it gives me firsthand experience of how far they will bend the law against perceived enemies.”Duterte’s office has denied he is involved in the prosecutions against Rappler. But the president has previously sparred with the company’s employees, and personally barred Ressa and another reporter from his official residence over their coverage of his administration. Earlier this month, a spokesperson for the president denied that the charges against Ressa and Rappler were politically motivated. Ressa said she encourages journalists around the world to “hold the line.””Every time you allow the government to cross it, you erode your own power,” she added. CNN’s Euan McKirdy and Bianca Britton contributed to this report.