This is the 18013th most frequent Korean word.
수사했다면
"수사했다면" means "if (someone) had investigated."
In this sentence, '수사했다면' is used to denote a hypothetical situation in the past where an investigation was conducted.
그 사건을 처음부터 제대로 수사했다면, 결과가 달라졌을 것입니다.
If the case had been properly investigated from the beginning, the outcome might have been different.
Here, '수사했다면' implies a conditional past action of investigation which might lead to further knowledge.
그들이 모든 증거를 철저히 수사했다면 우리는 더 많은 사실을 알게 되었을 것입니다.
If they had thoroughly investigated all the evidence, we would have learned more facts.
In this context, '수사했다면' is employed to express a presumed consequence following a past investigation.