From Longman Dictionary of Contemporary Englishcome down on somebody phrasal verbSTRICTto punish someone or criticize them severely We need to come down hard on young offenders. I made the mistake of answering back, and she came down on me like a ton of bricks (=very severely). → come→ See Verb table
Examples from the Corpus
come down on • Having contemplated the pro's and con's Darwin came down on the side in favour of marriage.• And you have the second line of management coming down on you.come down hard on• Judge comes down hard on acid attackers.• And not unexpectedly, the draft comes down hard on Dole and the tobacco industry.• I came down hard on her, because she was the weakest of all.• You'll find that Mr Evans comes down very hard on people who don't do their job properly.• The authorities are really coming down hard on tax evasion.• In the past the Securities and Exchange Commission has come down hard on trading systems that exclusively benefit institutions. 