A “benchslap” (judicial bench + bitchslap) is when a judge slaps down someone (such as a lawyer, another judge or the government) orally in court or in a written judicial opinion. The term was coined by David Lat, who wrote on the blog Underneath Their Robes on June 24, 2004:
 
“The title ‘Bench-Slapped!’ is derived, of course, is from the term ‘bitch-slap.’”
 
Josh Blackman’s Blog, on December 18, 2012, described eight different benchslaps.
 
   
Wikipedia: David Lat
David B. Lat (born 1975) is an American blogger and a former federal prosecutor. He is the founder and managing editor of Above the Law, a blog about law firms and the legal profession.
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Lat first began blogging under the pseudonym Article III Groupie, pretending to be a woman, for the judicial gossip blog “Underneath Their Robes,” until he revealed his identity in a November 2005 interview with Jeffrey Toobin of The New Yorker. Afterward Lat left his job as assistant U.S. attorney to write for the political blog Wonkette.
 
In August 2006, Lat launched Above the Law, a blog about law firms and the legal profession, for the Breaking Media network of sites.
     
Underneath Their Robes
JUNE 24, 2004
Bench-Slapped! Reinhardt v. O’Scannlain
WHACK! Consider yourself BENCH-SLAPPED! Welcome to the inaugural post of “Bench-Slapped! Article III Infighting,” dedicated to chronicling spats, feuds, and rivalries within the Article III judiciary.
 
The title “Bench-Slapped!” is derived, of course, is from the term “bitch-slap.” Lest you think Article III Groupie profane or uncouth, she would note for the record that this venerable term has been recognized by no less an authority than the Oxford English Dictionary, which defines “bitch-slap” (yes, it’s hyphenated) as follows: “to deliver a stinging slap to (a person), esp. in order to humiliate one regarded as inferior.” Considering that the Article III bench is occupied by 877 legal egos, many of them enormous, bench-slappery is inevitable—which is fortunate for us, because watching brilliant and distinguished jurists bench-slap each other silly is a deliciously guilty pleasure, Article III’s answer to female mud wrestling.
     
New York (NY) Times
NEW JERSEY
He Fought the Law. They Both Won.
By JONATHAN MILLER
Published: January 22, 2006
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Along the way Mr. Lat coined such terms as “litigatrix” and “bench-slap.”
 
Above The Law
05 Oct 2006 at 4:28 PM
ANTONIN SCALIA, BENCHSLAPS, FEDERAL JUDGES, SANDRA DAY O’CONNOR, STEPHEN BREYER, SUPREME COURT, WILLIAM PRYOR
An Anthology of Benchslappery
By DAVID LAT
judge william pryor bill pryor william h pryor jr.jpgJudge William H. Pryor, Jr., of the Eleventh Circuit, had an interesting op-ed in yesterday’s Wall Street Journal, in which he took issue with various “leaders of the bench and bar [who] have decried what they describe as unprecedented threats to the independence of the judiciary.”
     
Above The Law
23 Oct 2006 at 1:39 PM
9TH CIRCUIT, A. WALLACE TASHIMA, ASIANS, BENCHSLAPS, BETTY FLETCHER, ELECTION LAW, SUPREME COURT, SUPREME COURT CLERKS, WILLIAM FLETCHER
Benchslapped: The Arizona Voter ID Ruling
By DAVID LAT
passport united states passport.jpgWe realize we’re late on this, since the news broke on Friday. But at the time, we thought Purcell v. Gonzalez was just a run-of-the-mill Supreme Court ruling. We didn’t realize it featured delicious benchslaps of the Ninth Circuit, the lower court whose decision was vacated.
 
Urban Dictionary
benchslap
A benchslap is when a judge humiliates an attorney, insults another judge, or reverses a lower court in a particularly demeaning manner. A judicial bitch slap, if you will. This term was popularized by David Lat of AboveTheLaw.com (when he was blogging for UnderneathTheirRobes.com).
That was a classic Kozinski benchslap.
Judge Judy totally benchslapped that hooker that claimed to be a model, did you see that?
She might be a litigatrix, but that didn’t help her dodge that brutal benchslap.
by Count Christoph von Stoph-Stopherson October 18, 2007
 
Twitter
Above the Law
‏@atlblog
Quote of the Day: Well, cherries ARE delicious…. http://bit.ly/iyVcMy (Scalia benchslapping 9th Cir.)—DL - #SCOTUS
1:44 PM - 31 May 2011
 
Twitter
Bryan A. Garner
‏@BryanAGarner
How old is “bench slap”? Should I put it in Black’s Law Dictionary? How would you define it?
7:09 PM - 28 Nov 2012
 
ABA Journal
Is ‘Benchslap’ Worthy of Black’s Law Dictionary? Editor Tweets Question
Posted Dec 3, 2012 7:15 AM CDT
By Debra Cassens Weiss
The next edition of Black’s Law Dictionary could include the word “benchslap” if editor Bryan Garner can be persuaded.
 
Garner raised the issue in a tweet, Above the Law reports. “How old is ‘bench slap’?” Garner wrote. “Should I put it in Black’s Law Dictionary? How would you define it?”
 
Blogger David Lat says he was credited with origination of the term—which should be one word, not two—when he wrote for the blog Underneath Their Robes.
     
Josh Blackman’s Blog
DEC 18, 2012
The 8 Best Benchslaps of 2012
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1. Horizontal Bench Slap
The horizontal benchslap refers to a judicial remark that smacks down a fellow judge on the same court.
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2. Vertical Bench Slap
The vertical bench slap refers to a judicial remark that smacks down a judge on a lower court.
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3. GVRtical Benchslap
The most severe of all vertical benchslaps is when SCOTUS calls out a court of appeals by name in a Grant-Vacate-Remand (GVR in the lingo) per curiam order. This is the dreaded GVRtical bench slap (pronounced Go Vertical).
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4. Reverse Benchslap
The reverse benchslap (as coined by David Lat) refers to “a lower-court judge dissing a judge on a higher tribunal.”
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5. Best Flying Benchslap
Yet, the benchslap is not only used to smack down other judges. Frequently, it is used to smack down litigants who mess up. In such cases, the Judge flies off the bench to deliver a personal slap to the litigant. This is the flying benchslap.
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6. General Benchslap
Perhaps the least general of all benchslaps are general benchslaps, where a Justice smacks down the Solicitor General.
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7. Inter-Article Benchslap
When the benchslap is so hard, it stings from Article III to Article II to Article I.
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8. Lifetime Achievement Award for Benchslappery
Winners: Justice Antonin Scalia and Judge Richard Posner
 
Above The Law
23 May 2013 at 2:52 PM
ANTONIN SCALIA, BENCHSLAPS, CONSTITUTIONAL LAW, JOHN ROBERTS, POLITICS, SCOTUS, SUPREME COURT
Righteous Indignation: Conservatives Benchslapping Conservatives
By TAMARA TABO
Ed. note: This is the latest installment of Righteous Indignation, our new column for conservative-minded lawyers.
   
Washington (DC) Post
How Supreme Court justices ‘benchslapped’ each other in the Hobby Lobby case
BY AMANDA HOLLIS-BRUSKY July 1 at 9:58 AM
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Episodes of judicial tattling – court members calling one another out in writing – are nothing new. They have, however, become so frequent and visible of late that one blogger has coined a term for them – “benchslapping.”