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Gibbs's Rules are an extensive series of guidelines that NCIS Special Agent Leroy Jethro Gibbs lives by and teaches to the people he works closely with.


In Season 1's "Missing", Tony guessed that the rules originated with the Marine Corps, but Gunnery Sergeant Bill Atlas confessed that he had never heard of them.

On the other hand, during the Season 2 episode, Forced Entry (episode) when Rule Twenty-Three was once referred to during a case, a nearby MP quoted the rule correctly.

Later, in Season 6's "Heartland", Tony asked Jackson Gibbs whether he had taught the rules to Leroy, but Jackson ruefully said he hadn't managed to teach his son much of anything.

It was revealed in the last few minutes of "Heartland" that Gibbs's rules originated from his first wife, Shannon Gibbs, where she told him at their first meeting that "Everyone needs a code they can live by". The only rule of Shannon's personal code that is quoted is either her first or third: "Never date a lumberjack."

Years later, after their wedding, Gibbs began writing his rules down, keeping them in a small tin inside his home which was shown in the Season 7 finale episode, Rule Fifty-One (episode). Though he uses it often we almost never see the tin.

The knowledge of the rules's origins is left as a mystery to the people that Gibbs works with, though some of them do make concentrated efforts to find out. Anthony DiNozzo makes several attempts to find out who taught Gibbs the rules, though he has not yet met with any success.


At the beginning of her tenure with NCIS, during the Season 3 episode, Switch (episode) Gibbs informed Ziva David that there were approximately fifty rules that were his job to teach her.

Some years later, Gibbs added the "51" Rule to the tin he kept the rules in while according to Tony, seven of the rules directly concern lawyers, and that the eighth rule was inspired by a lawyer as revealed during the Season 6 episode, Collateral Damage (episode). Rule forty and above are not rules necessary for everyday life, they are for emergencies.

Although there are presumably at least 91 rules by the time of "Rule 91" in Season 18, not all of even the ones so far mentioned are in [list of Gibbs' Rules]. Currently, the list only includes rules up to Rule 69.

The Rules

Number Rule Referenced in Notes
1(1) Never let suspects stay together. "Yankee White" (Season 1);
"Ships in the Night" (Season 8)
According to McGee in "Ships in the Night", Rule Number One has actually been taken twice (see below).
1(2) Never screw over your partner. "Blowback" (Season 4);
"Need to Know" (Season 9)
2 Always wear gloves at a crime scene. "Yankee White" (Season 1)
3(1) Don't believe what you're told. Double check. "Yankee White" (Season 1) This rule appears similar to Rule #8.
3(2) Never be unreachable. "Deception" (Season 3), "Rule Fifty-One" (Season 7) However, Gibbs has been known to be intentionally unreachable at times, normally when going undercover on a whim to maintain cover.
4 The best way to keep a secret? Keep it to yourself. Second best? Tell one other person - if you must. There is no third best. "Blowback" (Season 4)
5 You don't waste good. "Baltimore " (Season 8)
6 Never say you're sorry. It's a sign of weakness. "Flesh and Blood" (Season 8) Referenced throughout the series (often with a smack to the back of the head), but not given a specific rule number until this episode. The rule is also a direct reference to John Wayne's catch phrase in She Wore A Yellow Ribbon: "Never apologize, mister, it's a sign of weakness." DiNozzo notes the connection in Hiatus Part 1.
7 Always be specific when you lie. "Reveille" (Season 1)
8 Never take anything for granted. "Probie" (Season 3) Gibbs also quotes it as being "Never assume" during "Rekindled" (Season 9).
9 Never go anywhere without a knife. "One Shot, One Kill" (Season 1) Sometimes quoted as "Never leave home without a knife" or "Always carry a knife."
10 Never get personally involved in a case. "Obsession" (Season 7);
"She" (Season 16)
In Obsession Anthony Dinozzo admitted to Gibbs that he has broken rule 10 again to which Gibbs responds "Yeah, that is the I've had the most trouble with:"

According to SECNAV Clayton Jarvis, in "Nature of the Beast" (Season 9), this is also the number one rule in Washington politics. In the concluding scenes of "She" (Season 16) Gibbs dispensed with this rule and burned the text of the rule in his fireplace.

11 When the job is done, walk away. "Semper Fidelis" (Season 6)
12 Never date a co-worker. "Enigma" (Season 1);
"Jet Lag" (Season 7)
13 Never, ever involve lawyers. "Collateral Damage" (Season 6);
"Rule Fifty-One" (Season 7)
According to DiNozzo in "Collateral Damage", Gibbs has seven rules that involve lawyers, but #13 is the "umbrella rule."
14 Bend the line, don't break it. "Anonymous was a Woman (Season 11)
15 Always work as a team. "Leap of Faith (Season 5)
16 If someone thinks they have the upper hand, break it. "Pyramid (Season 8)
17 Never, ever interrupt Gibbs during an interrogation. "Privileged Information (Season 14) Appears duplicative of Rule #22.

This IS rule 22.

Bishop just gave it the wrong number of 17.

It's NOT a duplicate.

18 It's better to seek forgiveness than ask permission. "Silver War (Season 3)
20 Always look under. "The Artful Dodger (Season 12)
22 Never ever bother Gibbs in interrogation. "Smoked (Season 4)
23 Never mess with a Marine's coffee... if you want to live. "Forced Entry (Season 2)
27 There are two ways to follow someone. First way, they never notice you. Second way, they only notice you. "Jack-Knife (Season 7);
"Rule Fifty-One."
28 When you need help, ask. "Blood Brothers (Season 13)
35 Always watch the watchers. "Baltimore" (Season 8)
36 If you feel like you are being played, you probably are. "Nature of the Beast" (Season 9)
38 Your case, you're lead. "Bounce" (Season 6);
"Phoenix" (Season 10)
Your is possessive. This is your cup, that's my cup.

You're is short for you are. You're lead. You're crazy. You're it

39 There is no such thing as coincidence. "Obsession" (Season 7) Although DiNozzo states that Rule 39A is "There is no such thing as a small world" during "Canary" (Season 10).
40 If it seems like someone is out to get you, they are. "Borderland" (Season 7) Abby and DiNozzo say that the rules in the 40s are for emergencies only and something unspeakable must be in play. (Season 7, episode 24)
42 Never accept an apology from someone who just sucker punched you. "Psych Out" (Season 9)
44 First things first, hide the women and children. "Patriot Down" (Season 7);
"Rule Fifty-One" (Season 7)
45 Clean up the mess that you make. "Rule Fifty-One" (Season 7) Also stated as "Never leave behind loose ends" in Hiatus Part 2.
51 Sometimes you're wrong. "Rule Fifty-One" (Season 7);
"Keep Your Enemies Closer" (Season 15)
Created by Gibbs by writing on the back of the card that states Rule #13 ("Never, ever involve lawyers.")
62 Always give people space when they get off an elevator. "Double Back" (Season 11)
69 Never trust a woman who doesn't trust her man. "Devil's Triangle" (Season 9)
72 Always be open to new things. "Spies Part 2 (NCIS: Hawaii (season 1)
73 Never meet your heroes. "A Thousand Words" (Season 16)
91 When you walk away, don't look back. "Rule 91" (Season 18)
99 Never tell Gibbs he's being audited. "Once Upon a Tim" (Season 16) Sloane said "being audited" not "been audited"

Although Nicholas Torres claims it wasn't an actual rule.

Unnumbered Rules

Rule Referenced in Notes
In my country, on my team, working my cases, my people don't bypass the chain of command. "Switch" (Season 3)
Don't work the system when you can work the people. "Hung Out to Dry" (Season 1)
Don't stop checking and rechecking evidence until you are satisfied. "Light Sleeper" (Season 3) Appears duplicative of Rule #3.
If you want to find something, you follow it. "Deliverance" (Season 6) According to Gibbs, he learned this one from Mike Franks.
Never second guess yourself in a relationship and life.

Other People's Rules

Person Rule Referenced in Notes
Abigail Borin #1. Never make excuses. "Ships in the Night" (Season 8) Only known rule thus far.
Abigail Sciuto #1. Do not lie to Abby. "Toxic" (Season 6)
#9. Always keep a spare. "Jeopardy" (Season 3)
Anthony DiNozzo #1. Don't sit on the sidelines while your people are in trouble. "Hiatus Part 2."
#3. Never underestimate your opponent.
Never date a woman that eats more than you do. "Singled Out" (Season 4)
Clayton Jarvis #1. Never get personally involved in a case. "Nature of the Beast" (Season 9) According to Jarvis, the Number One Rule in Washington politics.
Jimmy Palmer #1. Pipettes can never be too clean. "Restless" (Season 9)
Michael Franks You do what you have to do for family. "Spider and the Fly" (Season 8) The "Unspoken Rule"; implied to also be one of Gibbs's Rules.
Shannon Gibbs Never date a lumberjack. "Heartland" (Season 6) Either Rule #1 or #3.
Timothy McGee #1. Never lie to Gibbs. "Need to Know" (Season 9)
#70. Keep digging till you hit bottom. "The San Dominick" (Season 12) It is unlikely that McGee has seventy of his own rules; he presents Rule #70 as his own unofficial addition to Gibbs's rules.
Ziva David Knives don't run out of bullets. "Friends and Lovers" (Season 4) Mossad saying.


Although Gibbs has his list of rules to live by, he does not always adhere to them. One example is Rule #3. When Gibbs does not wish to be reached, he has been known to leave his cell phone behind. Except that many believe that to be one of Frank's rules since there are two Rule #3's. The other being 'Don't believe what you're told. Double check,' which sounds more like Gibbs. Also, on the anniversary of his last marriage, he unplugged his home phone and dropped his cell phone in paint thinner after his ex-wife began harassing him with phone calls. Gibbs also admits that rule number 10 is the one that he has had the most "trouble with" in "Obsession".

Gibbs broke Rule #1 (Never let suspects stay together) in "Ships in the Night" in order to get a confession. This also occurred in Caught on Tape (episode) but the suspects turned out to be innocent. Additionally, Gibbs broke the rule in A Man Walks into a Bar (episode) but the suspects were only guilty of covering up suicide, not murder.

Gibbs broke rule #13 (Never involve a lawyer) in Mother's Day (episode) Gibbs's ex mother in law becomes a suspect in a murder of a Navy officer. Gibbs contact Allison Hart, a lawyer, to represent her.

Gibbs also broke Rule #12 with former NCIS Director and partner in Europe, Jenny Shepard. Jenny was Gibbs' probie in their Europe missions and became romantically involved, which was ended by Jenny so she could lead her own team in Madrid. Although, since the relationship ended badly, some people suspect that this rule was created because of this relationship.

Another exception that Gibbs sometimes makes concerns Rule #6. Though Gibbs constantly tells people around him to never apologize, that it is a sign of weakness, he himself has apologized on at least seven occasions:

  1. To Caitlin Todd for being late to her funeral in Kill Ari Part 2 (episode).
  2. To Donald Mallard following his return from Mexico in Smoked (episode).
  3. To Joann Fielding for not being able to protect Shannon Gibbs and Kelly Gibbs in "Mother's Day".
  4. To Abigail Sciuto for frightening her and not being able to tell her what she wants to hear in "Rule Fifty-One".
  5. To the victim's lover for her loss, although he originally believes that she was being selfish in "A Man Walks Into a Bar".
  6. To Timothy McGee for not being with him when he was accused of shooting a cop in "Probie".
  7. To "The General" (Captain Wescott) in Shell Shock Part 2 (episode) for making him face a former serviceman and teammate, in which the encounter went poorly. Gibbs said, "That was my bad," for making Westcott agree to the meeting.
  8. To Mike Franks in Hiatus Part 2 (episode).

Though not shown, in "Semper Fidelis" ICE Agent Julia Foster-Yates claims that Gibbs and Fornell apologized to her for accusing her of murdering a coworker. McGee is shocked at the idea that either of them would apologize.

Gibbs also almost never accepts an apology from someone, preferring to simply offer correction to whomever made an error in an attempt to teach a lesson. One exception to this aspect of the rule was when McGee apologized concerning the situation with his sister, Sarah McGee in Twisted Sister (episode). Gibbs has also accepted some apologies because they are covered by rule #18: "It's better to seek forgiveness, than ask permission."

Also an apology isn't a sign of weakness if it's between friends, as Gibbs tells Dr. Mallard in "Smoked".

Although not strictly an exception, Gibbs did add a sort of corollary to Rule 39 concerning coincidences. In Head Case (episode) when Tony says, "We don't believe in coincidences around here," Gibbs added, "However, we do believe in bad luck."

In the same episode that Rule 17 was revealed, it was also made clear that an exception to the rule against interrupting Gibbs during an interrogation is if the information anyone in the NCIS Major Case Response Team uncovered was important and relevant enough to the case at hand that it was worth an interruption. Similarly, in Pay to Play (episode), it was revealed that while directly interrupting an interrogation was not allowed unless whatever information was uncovered was important enough to the case to make it necessary, sending a text to the person with Gibbs and bring him or her out if they uncovered anything in the case is tolerated.

Rule 10 was eventually retired in She (episode). This alongside some complications arising in ...and Executioner (episode) relating to the revelation of Gibbs' role in Pedro Hernandez's death as well as being forced to admit it to his team ultimately caused him to have a nervous breakdown before ultimately making peace with himself in Daughters (episode)


Throughout the series, there have been two rules referenced as the first and third of Gibbs' rules. For some time, it was believed that the duplications were either continuity errors or that the list of rules was meant to be malleable. Eventually, however, Executive Producer Shane Brennan revealed that the duplication was actually intentional:

"Gibbs lives his life by a set of rules that took root from the first day he met Shannon. Over time, Gibbs added to the rules. When he joined NCIS, Mike Franks told him he didn't need dozens of different rules to be an agent... just three 'golden rules.' And this is why we have double ups on rules #1 and #3. Three of them are Gibbs' rules; three of them are Mike Franks’ rules. We are still to reveal the double-up on rule #2. And it's up to the fans to guess which of the rules were Mike Franks’ three golden rules and which were Gibbs'.” (Shane Brennan's explanation of the duplication of Rules #1 and #3.) In spite of this, however, Franks seems to know Gibbs' rules as well as anyone, as evidenced in the episode "Patriot Down" when Gibbs passed the message "Rule #44" (First things first: hide the women and children) to him through Camilla.

The 40s

While most of the rules are for everyday use, Gibbs' rules 40-49 are considered emergency rules, to be invoked only in the most dire of circumstances. ("Rule Fifty-One") When Gibbs told Abby that rule 40 was in play, and Abby told Tony, he took it to mean that "something unspeakably bad is going down."