Clean Diamond Trade Act

Directs the President to require the appropriate Government agency to conduct annual reviews of the standards, practices, and procedures of any entity in the United States that issues Kimberley Process Certificates for the exportation from the United States of rough diamonds to determine whether they accord with the KPCS.

Makes the importing authority under this Act the U.S. Bureau of Customs and Border Protection (BCBP) and the exporting authority the Bureau of the Census.

Declares that the Congress supports the trade policy that the President take appropriate steps to promote and facilitate the adoption of the KPCS by the international community.

Sets forth civil and criminal penalties for violation of this Act.

Authorizes the President to direct the appropriate Federal agencies to make available technical assistance, relating to compliance with U.S. trade laws, to countries seeking to implement the Kimberley Process Certification Scheme.

Urges the President to work with Participants to strengthen the Kimberley Process Certification Scheme through the adoption of measures for: (1) sharing statistics on rough diamonds production and trade; and (2) monitoring the effectiveness of the KPCS in stemming trade in diamonds whose importation or exportation is not controlled through the KPCS.

Urges the executive branch continue to: (1) keep and publish statistics on imports and exports of rough diamonds; (2) make them available for analysis by interested parties and by Participants; and (3) take a leadership role in negotiating a standardized methodology among Participants for reporting such statistics.