Tool for the detective, not used for convictions.

用来作为侦探的工具而不是用来定罪。

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For some suspicious spouses, the GPS in their vehicle is another detective tool.

WSJ: Hiding Money From Your Spouse Has Gotten a Lot Harder

Tens of thousands of criminals are in prison today thanks to DNA, which has proven to be a detective's most valuable tool.

CNN: If DNA collecting banned, rapists will go free