Bluff VS Sense Motive

[Kerilstrasz]

A character wants to tell a lie to an NPC or PC...
He rolls a Bluff??? And the target of the bluff a sense motive??
lets say the bluffer tells a lie about smthing the S.Mot.er is at no position
to know if the info is real at all(for example:My father once told me that there were
that law in effect in that village)... that means what? bonus to bluff? the target believes him?
If the S.M.er has no reason not to believe the Bluffer, do they still have to roll
bluff & S.M. ???
in conclusion... a Maxed Out S.M. Char. with lucky rolls is effectively a lie detector???
Is S.M. a "passive skill" against lying? I mean, a character is always entitled to
a S.M. check when any1 he can hear or understand is telling a lie????

At the end...
What is the exact process of these opposed skills when smn telling a lie???

[KillianHawkeye]

Sense Motive is not just about believing or not believing what the other person is saying. It is also about reading the other person, i.e. body language or other indicators which tell if they are being honest or lying. In that way, a successful Sense Motive check tells you if the person is telling the truth regardless of whether or not you should have any knowledge of what they're talking about.

[ahenobarbi]

When a character lies it makes a Bluff check. Everyone who pays attention makes Sense Motive check.Listeners who got better result on Sense Motive check than liars Bluff check know that the character was lying.

Bonuses or penalties may apply (see Bluff skill description (http://www.d20srd.org/srd/skills/bluff.htm)). Characters who are aware of the lie don't know the truth (for example someone lied "i bought a black car", you know it's a lie but you don't know if I bought white cat, a dog or nothing...).

It's like sometimes you can tell people are not telling the truth (even if you have no idea what is truth or why would they lie at the moment).

[Andreaz]

A good bluff roll makes you give off the right impression. Confidence, certainty, fearfulness. A lie feels true because the guy speaks as if it was true.

A good sense motive roll lets you know "he's on to something", "he's hiding something" or "he's nervous about this". A bad sense motive draws you a blank: You sense nothing wrong about what he said.
Believing is entirely up to you.

[Yora]

It's also where the modifiers to sense motive come into play.

With false facts that seem perfectly plausible, the Bluffer only has to cover up any nervousness and make it look like he knows what he's doing, which is a normal Bluff roll and Sense Motive roll with no special modifiers.
If the false facts are hard to believe for the other person, he gets a bonus of +5, +10, or even +20 to the Sense Motive check, because he will want confirmation that the bluffer really meant what he thought he heard, which adds more mistakes the Bluffer can make while elaborating on his false story.

[Person_Man]

Here's the process I use, which is common in the groups I've played with, but is homebrew and not RAW.

At the start of a campaign, the DM asks each player what their Sense Motive check is. The DM adds 10 to this number for each player. This becomes their passive Sense Motive check.

Whenever an NPC attempts to lie to a player, he rolls a Bluff check. (The DM should preferably do this prior to the encounter itself, even if he isn't sure that the NPC will lie, so that player's aren't tipped off by the DM rolling dice behind his screen, and thus more prone to metagaming). If the Bluff check is higher then the passive Sense Motive checks of all the players who are present when he lies, then the NPC succeeds. If it is equal to or lower then the Sense Motive checks of any player, then those players are informed that the NPC is lying. How I convey this is based on the context of the Bluff and how well it succeeds or fails. (You get a strong sense that he is completely making this up, you get a vague sense that he may not be telling you the entire story, etc).

If the player has a legitimate reason to guess that an NPC is lying based on the context of the situation, they may instead choose to roll their Sense Motive check. (Though they may keep their passive check if they prefer). For example, if a player is interrogating an NPC, who obviously has an incentive to lie.

[Ashtagon]

As others have noted, Bluff is oposed by Sense Motive for most purposes.

However, if you are trying to Bluff someone on a topic about which they have specialist knowledge, they are entitled to use their actual Knowledge ranks about that subject or their Sense Motive ranks, whichever is higher. This reflects that, while you might not spot their general shiftiness of demeanour, you can nonetheless spot that he lacks the expert knowledge of the topic to use the usual keywords associated with the topic.

[TopCheese]

Here's the process I use, which is common in the groups I've played with, but is homebrew and not RAW.

At the start of a campaign, the DM asks each player what their Sense Motive check is. The DM adds 10 to this number for each player. This becomes their passive Sense Motive check.

Whenever an NPC attempts to lie to a player, he rolls a Bluff check. (The DM should preferably do this prior to the encounter itself, even if he isn't sure that the NPC will lie, so that player's aren't tipped off by the DM rolling dice behind his screen, and thus more prone to metagaming). If the Bluff check is higher then the passive Sense Motive checks of all the players who are present when he lies, then the NPC succeeds. If it is equal to or lower then the Sense Motive checks of any player, then those players are informed that the NPC is lying. How I convey this is based on the context of the Bluff and how well it succeeds or fails. (You get a strong sense that he is completely making this up, you get a vague sense that he may not be telling you the entire story, etc).

If the player has a legitimate reason to guess that an NPC is lying based on the context of the situation, they may instead choose to roll their Sense Motive check. (Though they may keep their passive check if they prefer). For example, if a player is interrogating an NPC, who obviously has an incentive to lie.

This is one of the things that a few of my friends hate about 4e. I always used it this way even before 4e came out, along with many other skills that the players shouldn't really know the results to.

[Kerilstrasz]

Is the careful phrasing of a lie prevents the rolls????
for example... Player X get a Gold piece from player's Z pocket, he then place it
in player's Z backpack. All these without any1 notice anything...
the next day Z realizes the Gp is missing, and asks "Who steal my Gp?"
If player X sais "I don't know" or "Not me" (which both answers are true, because
the Gp is still at Z's possession,even though Z doesn't know it), should X roll
a bluff?????

Edit:
Player X states "one time my Father told me that There was That law, held by Them."

The above statement is by all aspects a lie... but there are 4 factors... Father,There,That & Them.
Each or some of these factors may be untrue..
If player win the opposed S.M. , does he know if all of the above is lie, or he
can determine which of the factors are false? Because when X realize Z didn't
believe him he could answer "yes ok.. maybe it wasn't my father who mention it"
which is totally true... so Z may be cautious with the info but not certain that
it is untrue..

[Story]

Of course. Sense Motive doesn't care about the literal truth of what you say, it depends on how shifty you're being.

If the Sense Motive check succeeds, they know you're trying to hide something, but they don't necessary know what. If you try to respond with a partial truth, I think a second Bluff check is deserved.

[Kerilstrasz]

Of course. Sense Motive doesn't care about the literal truth of what you say, it depends on how shifty you're being.

im sorry.. can you rephrase plz.. got me a bit confused :)

[Twilightwyrm]

im sorry.. can you rephrase plz.. got me a bit confused :)

It doesn't matter as much what they are saying, it matters how they are saying it.

[Slipperychicken]

im sorry.. can you rephrase plz.. got me a bit confused :)

I despise that idea ("oh if I word it right I don't have to roll!"), and interpret Bluff to mean you still need to make a Bluff check if you say true words with the intent to mislead. The explanation is that a character may still be nervous or have suspicious body language, and must still attempt to act convincing, because he knows he is misleading the other. A failure on such a Bluff roll will give listeners a message like "This isn't the whole truth. He's leaving out something important." Even remaining silent may require a Bluff check, or else the Sense Motive guy knows "he knows something important, but won't talk".

[Person_Man]

Is the careful phrasing of a lie prevents the rolls????

Again speaking for myself as a DM and not RAW, I would say No.

Sense Motive should allow a player to Sense the Motives of NPCs (as normal humans can do in real life), not just a black and white lie detector. If someone is speaking in a lawyer-ly way, leaving out important details, twisting the meaning of words, or engaging in similar chicanery, you should have some chance to intuit it from their body language, tone of voice, choice of words, etc.

[Douglas]

I would allow careful phrasing, saying something that is misleading but technically true, to defeat Discern Lies, Zone of Truth, and similar things.

Sense Motive is all about attitude, body language, etc., though, and that kind of weasel-wording should not affect it.

[kardar233]

For my part, if a player managed to convince an NPC of something false using only statements that were technically true, I wouldn't make them roll Bluff, simply because I would be fairly impressed with their chicanery.

An example of this came along when we were playing a Pathfinder Society adventure that had the party masquerading as a spy team for an enemy organization, and nobody in the party had spent points on social skills. The character with the highest Charisma was the Paladin, who didn't want to tell any lies, but danced his way through the conversations and convinced the targets of their legitimacy without making any actual untrue statements. The DM ruled he succeeded and I heartily agreed.

[Andreaz]

For my part, if a player managed to convince an NPC of something false using only statements that were technically true, I wouldn't make them roll Bluff, simply because I would be fairly impressed with their chicanery.

An example of this came along when we were playing a Pathfinder Society adventure that had the party masquerading as a spy team for an enemy organization, and nobody in the party had spent points on social skills. The character with the highest Charisma was the Paladin, who didn't want to tell any lies, but danced his way through the conversations and convinced the targets of their legitimacy without making any actual untrue statements. The DM ruled he succeeded and I heartily agreed.Ugh selective bypassing.
make it a bonus to his bluff roll and carry on >.>