眾口鑠金

众口铄金
zhòngkǒushuòjīn
  1. lit. public opinion is powerful enough to melt metal (idiom)
  2. fig. public clamor can obscure the actual truth
  3. mass spreading of rumors can confuse right and wrong

CEDICT

the clamorous words or opinions of the mass may obscure the facts or turn lies into truth

Wiktionary

眾口所毀，雖金石猶可銷。語出《國語．周語下》：「眾心成城，眾口鑠金。」引申為眾口同聲，往往積非成是。如：「我們不怕事情有多複雜，只怕真相未白之前大家眾口鑠金，積非成是，到時候就麻煩了。」也作「群口鑠金」。

重編國語辭典

Entry Composition

1 眾 zhòng
  1. (bound form) crowd; multitude
  2. (bound form) many; numerous
2 口 kǒu
  1. mouth
  2. classifier for things with mouths (people, domestic animals, cannons, wells etc)
  3. classifier for bites or mouthfuls
3 鑠 shuò
  1. bright
  2. to melt
  3. to fuse
4 金 jīn
  1. gold
  2. chemical element Au
  3. generic term for lustrous and ductile metals
  4. money
  5. golden
  6. highly respected
  7. one of the eight categories of ancient musical instruments 八音 bāyīn