Washington, June 5 (RHC)-- The relatives of three Americans killed in U.S. drone strikes in Yemen without trial say they would not appeal the dismissal of their lawsuit against Obama administration officials.

The families of Muslim cleric Anwar al-Awlaki, his teenage son, Abdulrahman, and of Samir Khan had filed the suit accusing top U.S. officials of unlawful killings.

But in April, a federal judge ruled the victims’ constitutional rights were never violated, and said the U.S. officials involved cannot be held liable.

In a statement, the Center for Constitutional Rights and the American Civil Liberties Union said: "The U.S. government killed three Americans without due process. Getting answers in court should not be too much to ask in a democracy, but the system of checks and balances failed these families."