What technology allowed the police to identify criminals during this era and change detective work forever?

Forensics/DNA analysis.

Explanation:

This changed detective work because it allowed police to use even the smallest of evidence to catch a criminal. From a strand of hair to a fingerprint, detectives were now able to find criminals and store their DNA just in case they caused more crimes.

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lee and grant, both of whom held the highest rank in their respective armies, had known each other slightly during the mexican-american war (1846-48) and began their dialogue by exchanging awkward personal inquiries. characteristically, grant had arrived in his mud-splattered field uniform while lee had turned out in full dress attire, complete with sash and sword.

explanation: