U.S. Congress members held a hearing on Thursday to discuss a controversial new South Korean law that can send activists to prison or fine them thousands of dollars for sending informational flyers to North Korea.

The “anti-leaflet” law, which carries a maximum sentence of three years in prison or $27,200 in fines (30 million won) for violators, raised ire in recent months among human rights activists who send bibles, leaflets, USBs and other goods to North Korea. On Thursday, Republican New Jersey Rep. Chris Smith — who hosted the hearing— claimed that the law “infringes on freedom of expression” described in both the South Korean constitution and the International Covenant on Civil and Political Rights (ICCPR).