I am not legally trained, but my limited understanding is that libel is tested in a court of law . My view therefore is that something that may reasonably be referred to the courts for such a decision has the potential to be libellous.
potential
pə(ʊ)ˈtɛnʃ(ə)l/
adjective
1.
having or showing the capacity to develop into something in the future.
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[TR]
[TD=class: lr_dct_nyms_ttl]synonyms:[/TD]
[TD]possible, likely, prospective, future, probable, budding
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