Can you Investigate the same room twice?

Question

I have not seen this question when searching, although someone here might be able to point me to it. I found a related one here

Situation: PC walks into a room and wants to investigate to find any clues or whatever. They roll a 5 and lets say +3, which results in nothing. However, as a real person would, wouldn't the PC want to look again? In real life, if I'm in a room and I'm wanting to find something (imagine an escape room), I am going to continue looking around the same room. IE investigating it multiple times.

However, that seems broken, or at least too gamey. But I can't effectively call if gamey if it's a practice people do in real life.

So: Can you investigate the same room twice per RAW?

Answer 1

Yes, RAW allows you to investigate the same room twice

Multiple Ability Checks (DMG 237)

Sometimes a character fails an ability check and wants to try again. In some cases, a character is free to do so; the only real cost is the time it takes. With enough attempts and enough time, a character should eventually succeed at the task.

It then goes on with some suggestions on how to speed things up (automatic success by taking 10 times as long), and also that no amount of time can turn an impossible task into a successful one, or that failures can sometimes make subsequent attempts harder, depending on the situation.

So yes, repeats are allowed according to RAW.

Answer 2

Nothing in RAW prevents this, but ...

... the DM isn't required to have them roll again.

Let's get back to basics. From Basic Rules Chapter 1: (I added formatting for clarity)

1. The DM describes the environment.

2. The players describe what they want to do.

   • {snip} ...the DM listens to every player and decides how to resolve those actions.
   • Sometimes, resolving a task is easy. If an adventurer wants to walk across a room and open a door, the DM might just say that the door opens and describe what lies beyond. But the door might be locked, the floor might hide a deadly trap, or some other circumstance might make it challenging for an adventurer to complete a task. In those cases, the DM decides what happens, often relying on the roll of a die to determine the results of an action.
3. The DM narrates the results of the adventurers’ actions.

Unlike some versions of D&D where the player triggers/initiates the ability/skill check, in D&D 5e the DM is the one who calls for the die roll, or does not.

Ability Checks(Chapter 7: Using Ability Scores)

The DM calls for an ability check when a character or monster attempts an action (other than an attack) that has a chance of failure. When the outcome is uncertain, the dice determine the results.

In the above case, there was already a failure. If the DM is not given additional input from the PC on "what would be different about this second attempt at search" there is no compelling reason to roll again. But they can also allow that.

• As an example, it may be useful to allow that if the DM is using a 'ticking clock' kind of session where the players have to achieve "X" before event "Y" happens. At this point, the choice to "search again" or not has a consequence, but that consequence may or may not have nothing to do with finding anything in the room.

If the DM feels that another circumstance has influenced the room's condition, or the players perception (I put on my dark vision goggles!) to warrant a reassessment of the chance of success of failure, then a DM calling for the player to roll another check would make sense.

Sometimes a character fails an ability check and wants to try again. In some cases, a character is free to do so; the only real cost is the time it takes. (DMG p. 237)

The DMG (p. 237) has additional guidance for DM's to apply, at their discretion, regarding adjudicating ability checks.

When a player wants to do something, it's often appropriate to let the attempt succeed {or fail is implied if not stated} without a roll or a reference to the character's ability scores. For example, a character doesn't normally need to make a Dexterity check to walk across an empty room or a Charisma check to order a mug of ale. Only call for a roll if there is a meaningful consequence for failure.

When deciding whether to use a roll, ask yourself two questions:

• Is a task so easy and so free of conflict and stress that there should be no chance of failure?
• Is a task so inappropriate or impossible- such as hitting the moon with an arrow-that it can't work?
  If the answer to both of these questions is no, some kind of roll is appropriate.

There is some good advice in this Q&A here on multiple ability checks in general.

Answer 3

If they can try until they succeed, why is the DM calling for an ability check?

The DM calls for an ability check when a character or monster attempts an action (other than an attack) that has a chance of failure.

If failure has no consequences then it isn’t really failure.

And, no, losing time is not a consequence because time in a RPG is an infinite resource. As the DM I can make as much pass as I want in a sentence: “Later that day, ...” or even “Several decades pass ...”.

Now, time can be a limited resource but it has to be deliberately made one: the demon summoning ritual happens in 2 hours or you actually use time based wandering monsters that are more than a minor inconvenience.

Unless the difference between success and failure is going to force the player to make a decision about managing relevant resources then if it can be done in they way they are trying, they do it, if it can’t be done that way it rapidly becomes obvious that it can’t.

Answer 4

I can't speak for RAW, but in general, it's better to not allow senseless re-rolling of checks. It's meta-gamey and ruins the underlying assumption about probabilities of success associated with a skill level.

If there is no meaningful obstacle to them going over the room over and over, just let them take 20 instead of rolling, meaning you tell them what they can find, as long as they would have a chance of finding it at all. This should then of course take a long time, much longer than whatever you assume as time span for the single check.

If time is not unlimited, so using it to go over the room again is indeed a meaningful decision, then do allow them to re-roll, which of course includes spending that time for searching again. This would for example be the case in the escape room scenario: If you don't find anything on the first try, you try again, but the time lost is lost.

If time is not of the essence, I'd only allow the re-roll if the situation has meaningfully changed in between the attempts, for example, because the investigators have found a clue elsewhere and realized there should be a connecting clue in the first room as well. Or the players explain to you an approach which causes such a change in situation. For example, taking the furniture apart to check for hidden compartments, or flooding the room with water to see if there's any leaks in the floor.

Answer 5

RAW allows it, but there are considerations to take as a DM, based on this particular check

The accepted answer is best for the specific question and the RAW clarification, but you may want to consider on a case-by-case basis the re-rolling of ability checks depending on what is being done.

Players know that they rolled poorly, but their characters do not always know. It's easy to have observable failure on, say, an athletics check to kick down a door. It's less so obvious to a character that they failed to perceive something.

Often times when considering permitting a player to retry an ability check, I ask myself, "If I had rolled the ability check for the player and given the results without telling them the roll, would they still try again?"

Taking your question of searching a room, I would consider the goal of the character and the knowledge they have of what they are searching for.

• If the player is simply searching a room for "hidden doors or treasure" for the sake of it, the character would, on a failed check, simply assume their search was sufficient but there was nothing to be found.
• If the character was informed that the secret entrance to the bandit's lair was assuredly in that room, then it would be reasonable for the character to assume they need to search more thoroughly, and I would permit another check.

This concept extends to other scenarios as well, sometimes including several individual checks from other players:

• If the party asks the rogue to search for traps, and the rogue's player rolls terribly, the party's characters would not reasonably have a sudden distrust in the skills of their designated "trap guy" and start searching themselves.
• If the cleric's player rolls terribly during their interrogation of a suspect on an Insight check, the rest of the group's characters would reasonably accept the cleric's assessment of them "being truthful" and, while maybe still retaining an air of suspicion, would not continue to aggressively press the suspect until they pass the DC.

Answer 6

Why would you?

I mean, I know why the player would: because they rolled a 2, and they want a better roll.

But what the roll represents is the character doing whatever search they think is reasonable under the circumstances. Otherwise they'd keep searching, right? So if they roll a 2, they not only didn't find the thing, they also don't know they've missed anything.

The circumstances may constrain what a "reasonable" search looks like. If they're searching the room while the building is on fire, maybe they should have disadvantage. Conversely, if they have unlimited time and the freedom to completely tear the room apart, then they shouldn't even roll, because the outcome isn't in doubt.

Don't fall into the trap of thinking one die roll represents one "attempt" by the character to do a task (that if they roll an Investigation check for searching for 10 minutes, they can search for another 10 minutes and roll another Investigation check).

• The die roll establishes a fact: that you found the thing, or you didn't.

The only case where rolling multiple Investigation checks makes sense is if they don't get to search until they're satisfied, say because someone kicks them out of the room, and they later get the chance to come back and search it some more. But how much does it matter if they find it on the first attempt or the second? If they're that desperate to find the thing, you're probably making the mistake of hiding a plot-critical item or clue behind a failable skill check. In that case I'd let the Investigation check determine whether they find it before having to leave, or they have to sneak or fight their way back in to continue searching--at which point they will find the thing, without having to roll again, because seriously?

For more on this subject, see Justin Alexander's article "Let It Ride".

Answer 7

This may apply, I believe you can use the Action: Help too.

Help: You can lend your aid to another creature in the completion of a task. When you take the Help action, the creature you aid gains advantage on the next ability check it makes to perform the task you are helping with, provided that it makes the check before the start of your next turn.

A player may ask for a re-roll, but using Action: Help from another team member gains advantage on the ability check if declared to aid for a task.

I do have to admit, form me, like all things, the more crawlspaces, mines, basements, caverns, and caves I've been in, the less I look around. Once you've seen one, you've seen them all. It would take a special kind of person to hang around in them for 10 to 30 minutes while the rest party had no interest in them and moved on without you.

Answer 8

Use a passive check

Passive checks are designed for this kind of situation, where a PC is attempting something over and over:

A passive check is a special kind of ability check that doesn't involve any die rolls. Such a check can represent the average result for a task done repeatedly, such as searching for secret doors over and over again, or can be used when the DM wants to secretly determine whether the characters succeed at something without rolling dice, such as noticing a hidden monster.

Time may be important

Keep in mind that in an escape room there is usually a time limit. If played in D&D, players may have other things to do that sit there searching the room over and over again - they do not have unlimited time. Each Search attempt is time that could be spent sharing and comparing clues, discussing solutions, looking more closely at specific objects, etc. Examining existing clues and developing theories will aid in further investigations.

Investigation needs context

Remember that investigation is not perception. Even though the character sees that there are two pens on the desk, they may not realise they are suspicious or important until they find out that the killer wrote a note in ink. They need the context to understand what kind of clue they are looking for. The pens can be found with perception immediately, but until the players realise the pens are important, investigating them won't turn up anything. Once the killer's note is found, an invesitgation check may deduce which pen is the right one.

Answer 9

I consider an Investigation check a thorough process after which the character is certain they tried their hardest to search. Even if the player rolled a natural 1, the character thinks they did their best, so why would they investigate it again? I only allow these sorts of things after a certain amount of time has passed in which the character would reasonably think "Maybe I missed something... I should try again."

Think of the same question about a History or Arcana check. If the check fails, they don't know the information given. Thinking about it anymore probably wouldn't yield any more information.

Answer 10

RAW never makes an specifications on searching a room more than once. This is something left completely up to the DM's discretion for how to do it. Each DM has their own rules on how many times and how rooms and items can be checked, so always ask your DM.