翻译成英语：如果杀人是无罪的，我会杀了他

If kill him hadn't violate the law, I would have done
本句要使用虚拟语气的非真实条件句
1如果表示于过去事实相反的假设。
句型： 条件从句 主句 过去完成时 should(would) have+ 过去分词
If kill him hadn't violate the law, I would have done
2如果表示对将来的假想
句型： 条件从句 主句
一般过去时 should/would+ 动词原形
were+ 不定式 would + 动词原形
should+ 动词原形
If it was guiltless of killing him, I would do.

我觉得这个句子应该用虚拟语气（因为杀人不可能无罪，只是一种假设）

If murder was guiltless, I would kill him.

if it is guiltless of murdering, I will kill him

if it's guiltless for murder, i will kill him

If murder is innocent, I will kill him