- Легко очернить, нелегко обелить
- When you besmirch a per son's reputation, it is very hard for him to recover it See Дурная слава накрепко пристает (Д)
Cf: A bad wound is cured, /but/ not a bad name (Br.). An evil wound is cured, not an evil name (Br.). Give a dog a bad name and hang him (Am., Br.). Give a dog a bad name and his work is done (Br.). Give a dog an ill name, and hang him (Br.). Glass, china, and reputations are easily cracked and never well mended (Am.). A good name is sooner lost than won (Am.). An ill wound, but not an ill name, may be healed (Am.). An ill wound is cured, /but/ not an ill name (Am., Br.). A wounded reputation is seldom cured (Am.)
Русско-английский словарь пословиц и поговорок. Академик.ру. 2013.