As the saying goes, the net of justice is vast and lets nothing through; criminals will be punished in the end.
Tips
history
Adapted from 《老子·第七十三章》: 天网恢恢,疏而不失 ("Heaven's net is vast; loose, yet it loses nothing"). 法 (law) was substituted for 天 (heaven) in modern usage to apply the image to human justice rather than divine retribution.
usage
Standard rhetoric in Chinese crime news, court verdicts, and police PR. Often shortened to just 法网恢恢 in headlines.