Devibhagavatapurana 4.25.18

4.25.18

lokāpavādācca paraṃ tatastatyāja tāṃ priyām |
adūṣyāṃ dūṣitāṃ matvā sītāṃ daśarathātmajaḥ ||

Afterwards Râmachandra, the son of Das’aratha, had to banish his dear blameless Sîtâ on the mere ground of bad name, imputed to her by some ignorant person and that he would be thus blamed by the public.