An adviser to the European Union’s top court said Thursday Hamas and the Tamil Tigers should be taken off the EU’s terror list, because the bloc’s governments failed to present sufficient evidence that the groups participated in terrorist attacks.

The opinion of the European Court of Justice’s advocate general isn’t binding on the court’s judges. However, if confirmed, it would settle a yearslong court battle between the Palestinian and Sri Lankan groups and EU governments.

In 2014, the EU’s second-highest court ordered Hamas and the Tamil Tigers to be struck off the bloc’s terror list in two separate decisions. It said at the time that Hamas’s listing wasn’t based on evidence that had been properly examined and confirmed by national authorities, but on “factual imputations derived from the press and the internet.”

The European Council, which represents EU governments in the bloc’s lawmaking process, had appealed that decision, arguing that it was relying on a 2001 decision by the U.K. that designated both Hamas and the Tamil Tigers as terrorist groups as well as the terror listing for both groups in the U.S.

Thursday’s opinion rejects that argument, following similar reasoning as the 2014 decision. “The council cannot rely on facts and evidence found in press articles and information from the internet,” Advocate General Eleanor Sharpston said.

Ms. Sharpston also said that the council needed to present to the court information on attacks perpetrated by the groups, and cannot rely on terror listings by countries outside the bloc, such as the U.S., without ensuring that they had sufficient protection of fundamental rights.

A final judgment from the Luxembourg-based ECJ will likely take several months to arrive.

-Wall Street Journal 
-Agencies