Wife of Venezuelan opposition leader Lopez speaks in US

For 5-year-old Manuela, the "magic word" is not please or thank you, it's "libertad"—the Spanish word for freedom. That's the term she's heard her mother say repeatedly in the 15 months since her father, Venezuelan opposition leader Leopoldo Lopez, has been in prison.

"We are going to free daddy," Lilian Tintori told her daughter in Spanish during a roundtable at the Council on Foreign Relations on Wednesday.

Tintori was in Washington to accept an award on her husband's behalf from the nonprofit National Endowment for Democracy. While here, she spoke about her husband's situation to members of the Council on Foreign Relations, an influential foreign policy organization.

Leopoldo Lopez is escorted by the National Guard after turning himself in, during a demonstration in Caracas on Feb. 18, 2014.
Juan Barreto | AFP | Getty Images
Leopoldo Lopez is escorted by the National Guard after turning himself in, during a demonstration in Caracas on Feb. 18, 2014.

Her Washington trip comes as the health of the Venezuelan economy continues to hit new lows. The country's black-market exchange rate fell below 300 bolivars per U.S. dollar on Thursday. In 2012, a dollar exchanged for 10 bolivars, and even as recently as April 2013, when current President Nicolas Maduro was inaugurated, a dollar brought 24 bolivars.

Lopez, whose trial is underway, is accused of conspiracy and of inciting violent protests against the government. Last year, Lopez and other opposition leaders called for peaceful demonstrations against Maduro's government amid Venezuela's ongoing economic implosion.

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Venezuela's staggering inflation rate of 68.5 percent, its currency controls and lower oil revenue have generated scarcity of basic goods such as flour, toilet paper and medicine. Venezuelans stand in lines for hours outside supermarkets to buy whatever may be available.

Last year, a wave of violence after anti-government protests resulted in the deaths of dozens of protesters. That unrest marked the beginning of a political crisis Venezuela.

"Soon [Lopez] will have to see a prison because of his crimes," Venezuelan President Nicolas Maduro said last year in a televised address to the nation. "That fascist fugitive has to go to jail."

Lopez, a 44-year-old, former mayor, surrendered during a public demonstration shortly after Maduro called for his imprisonment.

"Leopoldo Lopez turned himself in for three reasons," Tintori told CNBC. "The first one, Leopoldo Lopez is innocent. We asked to release Leopoldo Lopez and all the political prisoners in Venezuela. The second, Leopoldo loves Venezuela and is never going to leave the country, and third, Leopoldo wants to unmask Maduro."

Tintori, a former kite-surfing champion and television host, has emerged as a human rights activist, trying to raise awareness about Venezuela's economic and social chaos. She has embarked on an international tour to ask world leaders for support for her husband's freedom. Ex-presidents of Colombia, Peru, Mexico and Spain are among the leaders supporting Tintori's cause.

Lopez is not alone. There are 89 prisoners being held in Venezuela for political reasons, according to a Venezuelan non-governmental organization. Among them are two other mayors from the opposition: Daniel Ceballo and Antonio Ledezma.

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"The government feels threatened," said Harold Trinkunas, senior fellow and director of the Latin America Initiative in the Foreign Policy program at Brookings Institution. "The Venezuelan government is increasingly arbitrary in the use of the law to target the opposition. There is an old joke in Latin America: 'For my friends, anything; for my enemies, the law.' (The) Maduro administration practices that."

Lopez's trial is expected to end this month. He is expected to be sentenced to 10 years in jail.

"Sometimes heroes have to be in jail," Tintori said. "We are going to get through this."