in light of; in view of; according to
Used to express that a judgment, decision, or action is based on a standard, rule, fact, or situation. Often follows nouns like 事実, 法律, 規則, 状況.
See also: に照らすと
事実に照らして判断する必要がある。
We need to judge in light of the facts.
法律に照らして、その行為は違法とされた。
In view of the law, that act was deemed illegal.
に照らすと is a conditional form meaning 'if we compare with...', while に照らして is a continuative form used to state a basis for judgment.
に基づいて means 'based on' and is more concrete, often used with data or evidence. に照らして implies a more evaluative comparison against a standard.
From the verb 照らす (to shine on, to compare) in its て-form, combined with the particle に. The expression literally means 'shining a light on something' and metaphorically extends to 'in light of' or 'in comparison with'.