Bury/hide your head in the sand
Definition 1 of 2
Pro Tip 1/3Negative Connotation
This idiom usually implies criticism towards someone's inaction or denial. 
Politicians often bury their heads in the sand when it's time to make tough decisions.
Pro Tip 2/3Metaphorical Visual
Imagine an ostrich hiding its head to feel safer; this visual can help remember the phrase's meaning. 
Companies can't just hide their head in the sand when environmental issues are raised.
Pro Tip 3/3Modern Context
Common in discussions about social, political, or environmental issues. 
You're burying your head in the sand if you think climate change isn't real.