The most common and most likely answer to this crossword clue is the 6 plus 9 letter word SELECT COMMITTEE
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More clues leading to the result SELECT COMMITTEE
- Choose dry red when touring with English MPs here
- Investigating politicians Sun preferred to execute, with little support
- Let’s cite memo, mistaken about European court, in parliamentary group
- Investigating MPs ‘southern elite’, pledge support
- Let's cite memo, mistaken about European court, in parliamentary group
Buddy explains!

The straight part
We know that "investigating politicians" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case investigating politicians = select committee.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.