Page "Who (pronoun)" Paragraph 30

In 1978 the who – whom distinction was identified as having " slipped so badly that is almost totally uninformative ".

According to the OED ( 2nd edition, 1989 ), whom is " no longer current in natural colloquial speech ".

Lasnik and Sobin argue that surviving occurrences of whom are not part of ordinary English grammar, but the result of extra-grammatical rules for producing " prestige " forms.