Possible Clues:

• Trenchant section of the law one's taken into account
• Like tart? Heavy metal band picks up two, separately
• Sharp US agents turn up to arrest British cops
• Sharp, a group of detectives in charge
• Cutting from papers I found in a volume
• Tart and custard isn’t desirable in courses — just starters
• Biting currents one repeatedly dives into
• Having a low pH value
• Like lemonade
• Ace detectives in charge becoming sour