be bad news

be bad news

slang To be, or be perceived as, unpleasant or unsavory. Stay away from that gang of kids from the other side of town—they're bad news. Coach lets me play a lot, so if he gets fired, it will be bad news for me. Our wedding is this weekend, so a snowstorm would be bad news indeed!
See also: bad, news
Farlex Dictionary of Idioms.

be bad news

COMMON If you say that someone is bad news, you mean that they have a bad character and are likely to cause trouble. We've separated and I'm glad. He was bad news.
See also: bad, news
Collins COBUILD Idioms Dictionary, 3rd ed.

be bad news

be a problem or handicap. informal
1996 City Paper (Baltimore) From the moment we see Mark Wahlberg… surrounded by pool-hall scumbags, we know he's bad news.
See also: bad, news
Farlex Partner Idioms Dictionary

be bad ˈnews (for somebody/something)

be likely to cause problems for somebody/something: Central heating is bad news for indoor plants.
See also: bad, news
Farlex Partner Idioms Dictionary
See also:
  • bad news
  • pill
  • the pill
  • come to a bad end
  • come to a bad/sticky end
  • bad company
  • do the deed
  • net result
  • get into bad company
  • get into/keep bad company