Question

Scenario: John was convicted of theft in 2015 and was sentenced to ten years imprisonment. In 2020, a new law was passed that reduced the penalty for theft to a maximum of five years imprisonment. John's lawyer argues that the new law should be applied retroactively to his case, resulting in a reduction of his sentence. The prosecution, on the other hand, contends that the new law should not apply retroactively and that John should serve the original ten-year sentence.

Question: Should the new law reducing the penalty for theft be applied retroactively to John's case? Explain your answer in light of the principles governing the retroactive effect of penal laws in the Philippines.