Answer:
The type of figurative language is 'metaphor' which is a figure of speech that makes an implicit or hidden comparison between two unrelated things.
Meaning of figurative language: in this case, the metaphor is explaining the attitude towards Jewish people in terms of law; it was 'illegal' to aid them.
Effect on tone and mood: the fact that it was forbidden to help and comfort the ones in need gives a serious tone and mood to this passage.
Effect on the audience: It portraits the suffering of Jewish people for having been discriminated against. It also makes more significant the figure of Martin Luther King.
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