Takagi knows Conan's identity (Theory)

[Chekhov MacGuffin]

While Conan speaks freely around Takagi there are still several things he keeps hidden from Takagi anyway, especially matters concerning the FBI and the Black Org. I don't think it makes sense to extrapolate that Takagi must know Conan's identity and be in on some of Conan's plans because Conan is willing to use Takagi while not hiding his personality. To demonstrate my point, here are two examples where Conan chose not to use or tell Takagi where Black Org or FBI information was involved which occurred after the Matsuda redux case. Conan did not try to ask Takagi to obtain a copy of the Itakura's diary disk, instead he chose a ploy to copy it himself using the police. (37-7) Instead of straight up telling Takagi that Camel was an FBI agent in the Shiranpuri case, Conan called Jodie so she could decide what to do. (58-8)
While Conan has used Takagi in situations involving what may potentially be the Org, such asking Takagi to talk to the people who followed Yukiko at the final screening case (41-6), that's not a situation where Takagi is put in direct danger. Takagi has plausible deniability about why he was asked to be there.

Also asking Takagi to do something like help trick Jodie about the fingerprints would imply that Conan is asking Takagi to break the law or at the very least fail to do his duty as a police officer. I am not sure Takagi would be willing to go that far; helping Conan conduct an investigation to solve a crime is one thing, but not questioning Conan when Conan is clearly is connected criminal acts is a different deal. Takagi has been consistently characterized as upright and moral about doing his duty even when he was tempted to do other things (like go rescue Sato from Shiratori), so putting his trust of Conan ahead of being a good officer would be out of character for him. One thing to note is that the police don't seem to know the identity of the body. Jodie never gave a name to her cellphone-finding man from the road-side restaurant. The police don't know Akai is FBI related.
Even if Conan didn't tell Takagi why he wanted to trick Jodie about the body, Takagi could figure out several very incriminating things. The first is that Conan is withholding evidence or was involved in a crime related to the dead body in the Chevrolet. The police concluded the crime was a homicide and that means Conan asking Takagi to disguise or lie about the body implies Conan knows something about the murder and isn't spilling. It would be a serious failure of protocol not to question Conan or Jodie whom information is being hidden from, especially since she is FBI, and there may be some motive related to her job.
If Takagi did know that Conan was helping some man fake his death, Takagi would begin to question the circumstances. Somehow Conan and friends managed to find a dead body. How, why, and was there a crime attached to it? Also, why does someone need to fake his death in the first place; who tried to kill him? Takagi could probably also guess it was related to the FBI when Jodie came looking for a fingerprint match with Conan's cellphone. Why is the FBI involved in Japan because being on vacation and looking for information about someone who faked his death doesn't mesh.
Good luck in trying to find a posting pattern. : P

[Dus]

*opens topic*
*sees Chekh*


And, yes, Conan would never get Takagi involved and I doubt that Takagi would help him without asking any questions. Conan didn't get the cops involved in volume 1, so why should he start doing so now, when it would pose various problems, as Chekh pointed out.

[Stopwatch]

...
So, if Takagi didn't know about the fingerprints two questions are raised.
1) Why did he have a spare of Conan's phone?
2) Takagi specifically says 'Conan's' fingerprints were on it, does this mean that Vermouth was disguised as Takagi then or that he just presumed they were Conan's were Conan's based on the size..?
EDIT; The 'Shinichi-kun' thing though, I still can't figure out how to think of  it in any other way than Takagi knowing Shinichi = Conan. Has anyone else come up with any plausible alternate suggestions...? 

[Abs.]

1) Why did he have a spare of Conan's phone?

Who? If you're asking about the phone Takagi examined, Jodie gave it to him.

2) Takagi specifically says 'Conan's' fingerprints were on it, does this mean that Vermouth was disguised as Takagi then or that he just presumed they were Conan's were Conan's based on the size..?

In the same file, Jodie specifically tells Takagi that her prints and Conan's prints are on there.

[Stopwatch]

I was talking about the phone that Jodie gave back to Conan that had been given to her by Takagi.

On the other point I meant that when Takagi returns with results he confirms that Jodie's and Conan's fingerprints were the other ones left on the phone.  I was saying that if Takagi checked Conan's by the database it would also come back as Shinichi's so either he:
1) Knows or suspects Conan 'cause of this.
2) He didn't check Conan's by the database and only checked them by size.
3) It wasn't Takagi in that scene and that's why he doesnt seem that suspicious. It's worth noting that Vermouth's motorbike came from the direction that Jodie came from.

[miakakiri]

I think my overall take on this matter is that Takagi knows (or at least strongly suspects) that Conan is actually Shinichi, but he doesn't know why, and he hasn't got any evidence he can use as proof so he mostly keeps his mouth shut.
This puts him in much the same position as Hakuba-kun, who is positive that Kuroba Kaito is the Kaitou KID (MK manga) but again has nothing he can use to prove this. Takagi, however, is more mature and doesn't see any point to needling Conan about it. I think he's waiting for Shinichi to decide if he wants to let anyone else in on what's happening.
I may have had more to say....but.... ~_~* Mind-blank. Sorry.

[Abs.]

I was talking about the phone that Jodie gave back to Conan that had been given to her by Takagi.

Takagi had that phone because Conan gave Jodie his phone to use, and Jodie gave that phone to Takagi to be examined.

On the other point I meant that when Takagi returns with results he confirms that Jodie's and Conan's fingerprints were the other ones left on the phone.  I was saying that if Takagi checked Conan's by the database it would also come back as Shinichi's so either he:
1) Knows or suspects Conan 'cause of this.
2) He didn't check Conan's by the database and only checked them by size.
3) It wasn't Takagi in that scene and that's why he doesnt seem that suspicious. It's worth noting that Vermouth's motorbike came from the direction that Jodie came from.

We don't know how the fingerprint comparison process works in-world, so we don't know that there is such a computer that they put the prints into that will just be like: "Okay these prints are Jodie's, these prints are Shinichi's, and these prints are that one guy's" - Actually if there was such a computer it would have said "And these prints are Akai Shuuichi's" since the police likely had to take prints from him during the bus hijacking due to his role in that (where they made him look like one of the kidnappers).

[Stopwatch]

I was talking about the phone that Jodie gave back to Conan that had been given to her by Takagi.

Takagi had that phone because Conan gave Jodie his phone to use, and Jodie gave that phone to Takagi to be examined.

That phone that Conan gave to Jodie ended up as evidence and Takagi gave Jodie another one to give to Conan 'cause of that. I'm talking about why Takagi even had an identical phone to Conan's to give to Jodie.
I'll say about your second point tomorrow 'cause I don't think I'll be able to come up with a logical argument at the moment so it's probably better to wait 'til I'm more awake. Though, didn't the Shiragami case have something about in universe fingerprinting...

[Abs.]

I was talking about the phone that Jodie gave back to Conan that had been given to her by Takagi.

Takagi had that phone because Conan gave Jodie his phone to use, and Jodie gave that phone to Takagi to be examined.

That phone that Conan gave to Jodie ended up as evidence and Takagi gave Jodie another one to give to Conan 'cause of that. I'm talking about why Takagi even had an identical phone to Conan's to give to Jodie.

Ah, right. Forgotten about that. At the time, I put it down to "the police have their resources"... MAYBE TAKAGI BUGGED CONAN'S PHONE ASDFOIDSJOIEDSIK

[thorongil]

it shouldn't be so hard to buy the same model somewhere...
concerning fingerprints... i think in this case its most likely that they just compare given person + phone... they don't need a suspect or anything and therefore they most likely don't use fingerprint databases, at least not for conan's and jodie's

[blackgin]

If Takagi and Sato continued to pursue it.

Bright Side:

Conan will have easy access to every crime scenes wherever it maybe. 

They finally call him "Kudo-kun" but they keep his identity a secret just like the rest of the people who came before them.

Dark Side: 

It might be the end of their careers because the investigation is considered illegal without the authorization from the Higher-Up.

The BO will make targets out them, if they find out about it. 

[miakakiri]

I'll say about your second point tomorrow 'cause I don't think I'll be able to come up with a logical argument at the moment so it's probably better to wait 'til I'm more awake. Though, didn't the Shiragami case have something about in universe fingerprinting...

The fingerprints thing in the Shiragami case was a simple matter of 'compare the fingerprints on the chain to the fingerprints on the knife'. It therefore has no bearing on this discussion. I suspect the phone thing was similar--Takagi-keiji was only comparing the fingerprints of the deceased to the various fingerprints on the phone, not ID-ing all the fingerprints on the phone.

On another note: While I think Takagi has some knowledge, I don't think Satou does. We're flat-out told in cannon (the highway case) that she's never met Shinichi (or Heiji) before he shrank. She's HEARD of him, yes, but she hasn't MET him, and is indeed impressed and almost weirded out by the kokosei-tantei's abilities when she encounters them. Satou-keiji make think something's odd with Conan-kun, but she doesn't have the background to make the guess that Conan and Shinichi are the same person. Takagi, who has known Shinichi as himself and seen him interact with Ran, DOES have that background information and therefore can conceivably make the connection.
I do think the line in the elevator with the bomb (episode 304) is highly significant to Takagi's dealings with Shinichi/Conan, and probably strongly influences any suspicions Takagi has. Eh, scratch the line, the whole incident really leads into that. It's Shinichi on full blast, Conan barely covered enough to keep from being too terribly obvious to anyone outside of the elevator. Shinichi is obviously aware in that instance that Takagi is suspicious of him, and may even have made a (very good) guess as to who he truly is, thus prompting the question more for confirmation than anything else.

Again: Takagi will not say/do anything on his own about Shinichi, because he has no proof.

[Abs.]

Also: Teenagers shrinking several feet in size? That's crazy talk.

[Borealis]

I think that Takagi is very aware of the fact that Conan defenitely NOT simply a little child. However, different from Heiji and the other teenage-detectives, he knows well enough what is likely too hot for him to handle.
If he suspects that Conan is Shinichi, it surely wouldn't be the only thing he takes into consideration. (eg: Conan is really a distant (or not so distant) relative of Shinichi who was raised very strictly)
consider: we have no information on his background (althoe he is one of the most important police officers), he might be related to some japanese secret agent, as far as we know. Or even to the BO.

[blackgin]

I think that Takagi is very aware of the fact that Conan defenitely NOT simply a little child. However, different from Heiji and the other teenage-detectives, he knows well enough what is likely too hot for him to handle.
If he suspects that Conan is Shinichi, it surely wouldn't be the only thing he takes into consideration. (eg: Conan is really a distant (or not so distant) relative of Shinichi who was raised very strictly)
consider: we have no information on his background (althoe he is one of the most important police officers), he might be related to some japanese secret agent, as far as we know. Or even to the BO.

He'll already notice that Conan act mature for his age. 

Its like talking to an adult.

This happen too with Akemi Miyano and Shiho Miyano when they are talking about Conan at a coffee shop.