In my opinion, in my judgement.
me judice/ˌmiː ˈdʒuːdɪsiː/ /ˌmeɪ ˈjuːdɪkeɪ/
Late 16th century; earliest use found in Thomas Nashe (d. c1601), writer. From classical Latin mē iūdicē, lit. ‘me being the judge’ from mē, ablative first person singular pronoun + iūdicē, ablative of iūdex.
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