The former Sinn Féin leader denies the allegation, and a jury has found the publication wasn't in "good faith", and it wasn't fair or reasonable to publish.
Gerry Adams is to be awarded €100,000 in damages, after winning his defamation case against the BBC.
The 76-year-old sued the broadcaster over a 2016 TV programme and online article, which claimed he sanctioned the killing of Denis Donaldson.
The former Sinn Féin leader denies the allegation, and a jury has found the publication wasn't in "good faith", and it wasn't fair or reasonable to publish.
Director of BBC Northern Ireland, Adam Smyth, said they are disappointed with the verdict.

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