From Longman Dictionary of Contemporary Englishlightning rodˈlightning ˌrod noun [countable] American English 1 a lightning conductor2 someone or something who gets most of the criticism, blame, or public attention when there is a problem, although they may not be responsible for itbe a lightning rod for something The senator has become a lightning rod for criticism.
Examples from the Corpus
lightning rod• Since then, she has become a lightning rod for a national debate on immigration.• It was like a lightning rod that drew to itself all the negative impulses of a hyperactive time.• One of the summer associates in another firm told me that a partner there had proved a real lightning rod for trouble. 