on dangerous ground
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on dangerous ground
In a position that poses danger to oneself or is likely to upset or offend others. I may be on dangerous ground with this opinion, but, as a mother myself, I really don't think women should breastfeed in public. You're on dangerous ground as long as you continue to antagonize him—I've seen him become violent.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.