The most common and most likely answer to this crossword clue is the 14 letter word INDISCRIMINATE
I've seen this crossword clue in The Sunday Telegraph
I
N
D
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More clues leading to the result INDISCRIMINATE
- Overly broad daughter is cutting finger
- Elected minister, cad, I suspect promiscuous
- Diamonds one's put in frame for sweeping
- One minister, I finally concluded, can work without discernment
- Daughter is in grass on blanket
- Daughter is framed by charge chosen at random
- Charge over diamonds is arbitrary
- Incendiarism — it could be thoughtless and chaotic
- Promiscuous daughter is put in frame
Buddy explains!

The straight part
We know that "chosen at random" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case chosen at random = indiscriminate.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.
What does INDISCRIMINATE mean?
INDISCRIMINATE adjective- Without care or making distinctions, thoughtless.