D&D 5E Passive Investigation?

[iserith]

While passive Investigation is not specifically called out in the final rules, there is a sidebar indicating that just about any skill can be used passively by taking the modifier and adding 10.

For my purposes, I tend to only keep track of the PCs' passive Insight and Perception scores, as those seem to me to be the two skills that are more passive than active anyway. I sometimes go with passive knowledge scores, and I've also started using passive Initiative in one of my games. But I've yet to actually use passive Investigation.

My issue with the Observant feat is that it doesn't really make sense to me that someone would be better at noticing things when they're *not* actively looking for them. Surely the feat really ought to grant advantage on active checks as well as the +5 advantage-equivalent to the passive scores.

Consider that "passive" refers to the fact that the player is not rolling any dice, not that the character is not doing a thing actively. If you take a look at the rules on passive checks, you'll see that's what it is referring to. Passive checks are used when the DM wants to make a check secretly and/or for when the DM wants to resolve uncertainty in a task that is being performed repeatedly.

In the case of passive Investigation, a character might be trying to deduce the significance of the faded hieroglyphs on the walls of the dungeon as the party travels its halls and chambers. (That the hieroglyphs are faded and the characters are traveling is perhaps what makes the outcome uncertain.) If the character's passive Investigation is high enough, then the character is able to arrive at a chilling deduction: That these hieroglyphs warn of a terrible curse that will befall any who desecrate the inner sanctum of the dungeon at the threshold of which the party now stands.

Unlike passive Perception, passive Investigation is probably not likely to come up a bunch, though of course that depends on the DM.

 

[pukunui]

[MENTION=97077]iserith[/MENTION]: It still doesn't sit right with me that the bonus only applies to the passive score and not its equivalent active check. +5, as we know, is essentially the passive form of advantage, so I reckon that the feat ought to grant advantage on active Perception and Investigation rolls as well. Maybe that's too powerful, but then a flat +5 to passive Perception is pretty darn powerful too.

 

[psychophipps]

I'm playing a variant human rogue investigator/arcane trickster and I see the Observant feat as the character is simply "switched on" all the time as stated by the actual RL investigator before (sorry, but Tapatalk makes it harder to flip back and forth to check names while posting). There are just some people that naturally notice things that most folks overlook because it doesn't occur to them to even care about them in their daily lives.
Now at 4th I will also take Keen Mind to crank the "D&D Sherlock Holmes" to 11...

 

[Li Shenron]

While passive Investigation is not specifically called out in the final rules, there is a sidebar indicating that just about any skill can be used passively by taking the modifier and adding 10.

This is true, although I don't know what sidebar you're talking about, even in Basic this is spelled out in the open

Passive Checks
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.

Here’s how to determine a character’s total for a passive check:

10 + all modifiers that normally apply to the check

If the character has advantage on the check, add 5. For disadvantage, subtract 5. The game refers to a passive check total as a score.

For example, if a 1st-level character has a Wisdom of 15 and proficiency in Perception, he or she has a passive Wisdom (Perception) score of 14. The rules on hiding in the “Dexterity” section below rely on passive checks, as do the exploration rules in chapter 8.

Passive checks are not restricted to "reactive" (vs "proactive") skills only! They represent routine tasks or tasks that extend over time and may include multiple instances at different instants and locations.

So you can freely use e.g. passive charisma to determine how a PC manages to mingle well in an unfamiliar social environment, or passive Artisan's Tools check to gauge the outcomes of practicing a crafting profession (not that passive checks rules aren't restricted to skills so they could also be unskilled ability checks or tools checks).

 

[pukunui]

Huh. I could've sworn it was in a sidebar. Maybe it was in the playtest rules.

 

[miniaturehoarder]

Passive investigate is pretty much gone from the rule set. Doesn't really matter either since that feat is plenty strong as it is.

 

[Li Shenron]

Passive investigate is pretty much gone from the rule set.

How can you say that when the Passive Checks rule specifically mention searching for secret doors?

 

[Athinar]

DMG
find a secret door by actively searching the location where the door is hidden and succeeding on a Wisdom (Perception) check. To set an appropriate DC for the check, see chapter 8.
Opening a Secret Door. Once a secret door is detected, a successful Intelligence (Investigation) check might be required to determine how to open it if the opening mechanism isn't obvious. Set the DC according to the difficulty guidelines in chapter 8.

Secret Doors normally have a check of 20, a normal Passive Wisdom (Perception) will never find a secret door, but I could be wrong

PHB
If the character has advantage on the check, add 5. For disadvantage, subtract 5. The game refers to a passive
check total as a score.

 

[Psikerlord#]

I found using passive perception vs static trap Dc = fail.

So I dont use any passive stuff at all. I just roll. I also substitute wis perception with int investigation anytime the players want (their choice).

Works well.

Obs feat gives adv on perception/investigation in my game.

 

[Glen Klepic]

Does the difference between a Passive Check and a Standard Check lie “in game”? This is suggested by the very term, “Passive” as opposed to “Active”. Take a Perception Check for example. The “in game” difference being that with a Passive Perception Check, the character is generally aware of his surroundings and may notice something, as opposed to with a Standard or “Active” Perception check where the character is actively searching for something and may find it. Page 177 of the PHB (in the section regarding Hiding) also hints that the difference lies “in game”. If this is the case, then when the character fails the Passive Check, he should then be able to attempt a Standard, or “Active” Check.


Or does the difference lie “out of game”, as suggested on page 175 of the PHB, under the heading of Passive Checks? The “out of game” difference being that with a Standard Check the player or the DM rolls a d20 (and adds modifiers) to determine the result, while with a Passive Check the player or the DM “takes 10” rather than actually rolling the d20 (and adds modifiers) to determine the result. In either case, the character must be actively making an attempt.

If this is the case, then the rule for Observant on page 168 that allows for a +5 bonus for Passive Checks should also allow it for Active Checks.

Conclusion:
It is unfortunate that the Player’s Handbook uses the term “Passive” to describe the “out of game” practice of “taking 10” when making an ability check. When describing the practice of "taking 10", the term “Passive Check” should be replaced with something like “Averaged Check” or “Automatic Check”. The opposite of this “Averaged Check” is a “Rolled Check” where the player or the DM actually rolls the D20 instead of “taking 10”. “Passive” should only be used to describe the “in game” situation where the character is not actively making some type of attempt. The opposite of this should be called an Active Check. Passive Checks (as opposed to Active Checks) are very often Averaged Checks (as opposed to Rolled Checks), but either a Passive Check or an Active Check could be made as a Rolled Check (by rolling the D20) or as an Averaged Check (also known as “taking 10”). In the case of a Constitution Check (such as going for long periods without food or water) there would be no difference between a Passive Check and an Active Check and only one or the other should be attempted. But in the case of a Perception Check, an Investigation Check, and possibly others, there is a definite difference, so after failing the Passive Check the character should be allowed to attempt an Active Check if he thinks of doing so. I was thinking that there should be some penalty for the Passive Check (such as a -5), but then I read the post above, written by Defcon 1. I think he was on to something. Any Passive Checks (as opposed to Active Checks, not as opposed to Rolled Checks) could use a simple Ability Check that does not include the player's Proficiency Bonus. That would, in affect, give the penalty to Passive Checks that I was considering.
I'm still digesting some of the other stuff that Defcon1 wrote, and I liked Duggage's train of thought although I don't think I entirely agree with his conclusions. I hope to get back to you on these things later.