Mr Justice Tugendhat will give his decision on the meaning of an allegedly libellous tweet she sent after a Newsnight report that wrongly implicated the Tory peer in child sex abuse allegations.
Earlier this month the judge reserved his decision in the case.
If the judgment goes in Lord McAlpine's favour, there will be another hearing at a later date on the appropriate level of damages, unless the two sides reach a settlement.
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What's your opinion on parents being told by headteachers they will be reported to police if they let children play over 18 computer games
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Parents have been told by teachers they'll be reported to police and social services if children to play Call of Duty or Grand Theft Auto