President Trump is being accused of witness tampering after he used his Twitter account to urge one of his top associates not to co-operate with Special Prosecutor Robert Mueller who is investigating Russian interference in the 2016 election campaign.
Legal scholars in the US say the President's Tweet could be construed as an attempt to obstruct justice, as our Washington Correspondent Simon Marks reports.
IN: "In a series….."
OUT: "…obstruction of justice charges"
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