"For a fictional portrait to be actionable, it must be so accurate that a reader of the book would have no problem linking the two," said Mr. Friedman. Thus, he continued, libel lawyers have what is known as "the small penis rule". One way authors can protect themselves from libel suits is to say that a character has a small penis, Mr. Friedman said. "Now no male is going to come forward and say, 'That character with a very small penis, that's me!'"
In Nebraska Law Review: Bulletin, Professor Michael Conklin writes that the use of the small penis rule would be ineffective to defend against defamation lawsuits. The reasons given are that the statement that a person has a small penis can be taken as defamatory in itself; the use of the rule is effectively an admission that defamation did occur; and the libelled person need not necessarily admit to having a small penis in order to claim damages. Conklin argues that its effectiveness is that the potential humiliation of being associated with a character with a small penis may deter legal action from being initiated.
The small penis rule was referenced in a 2006 dispute between Michael Crowley and Michael Crichton. Crowley alleged that after he wrote an unflattering review of Crichton's novel State of Fear, Crichton included a character named "Mick Crowley" in the novel Next. The character is a child rapist, described as being a Washington, D.C.–based journalist and Yale graduate with a small penis.
In response to being snubbed by former classmate Martin Amis, crime writer Peter James included in his novel Not Dead Yet a villainous character named Amis Smallbone. In the novel, Smallbone's penis is mocked by a prostitute, who refers to it as "like a tiny little pencil stub". The television show QI, while discussing the small penis rule, cited Amis Smallbone as an example.
- Dinitia Smith (24 October 1998). "Writers as Plunderers; Why Do They Keep Giving Away Other People's Secrets?". The New York Times. Retrieved 21 May 2013.
- Michael Conklin, The Big Problem with the Small Penis Rule: Why It Does Not Limit Defamation Liability, NEB. L. REV.: BULL. (March 17, 2021), Available at SSRN: https://ssrn.com/abstract=3750267 or http://dx.doi.org/10.2139/ssrn.3750267
- Felicia R. Lee (14 December 2006). "Columnist Accuses Crichton of 'Literary Hit-and-Run'". The New York Times. Retrieved 21 May 2013.
- Cole Moreton (27 May 2012). "Peter James: how I hit back at my stalker – and Martin Amis". The Sunday Telegraph.
- "Justice". QI XL. Season J. Episode 12. 8 December 2012. Event occurs at 12:08.