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Forensic Experts Say Screams Were Not Zimmerman's

Hugh Pickens writes "As the Trayvon Martin controversy splinters into a debate about self-defense, a central question remains: Who was heard crying for help on a 911 call in the moments before the teen was shot? Now the Orlando Sentinel reports that Tom Owen, a leading expert in the field of forensic voice identification sought to answer that question by analyzing the recordings. His result: It was not George Zimmerman who called for help. Owen, forensic consultant for Owen Forensic Services LLC and chair emeritus for the American Board of Recorded Evidence, used voice identification software to rule out Zimmerman. Another expert contacted by the Sentinel, utilizing different techniques, came to the same conclusion. Owen used software called Easy Voice Biometrics to compare Zimmerman's voice to the 911 call screams. 'I took all of the screams and put those together, and cut out everything else,' says Owen. The software compared that audio to Zimmerman's voice and returned a 48 percent match. Owen says to reach a positive match with audio of this quality, he'd expect higher than 90 percent. Owen cannot confirm the voice as Trayvon's, because he didn't have a sample of the teen's voice to compare however 'you can say with reasonable scientific certainty that it's not Zimmerman.'"

40 of 1,046 comments (clear)

  1. In case you missed it by AdmiralXyz · · Score: 5, Informative

    Zimmerman's claim of being badly beaten up before he shot the kid doesn't hold up either: there's some footage taken at the police station the night of his arrest, and he looks totally unharmed. No cuts to the back of the head, no broken nose, nothing. Guy's story has more holes than... eh, I'm on my eighteenth hour without sleep due to a project and can't come up with an apt metaphor, but something with a lot of holes.

    --
    Dislike the Electoral College? Lobby your state to join the National Popular Vote Interstate Compact.
    1. Re:In case you missed it by Anonymous Coward · · Score: 5, Funny

      More holes than Trayvon?

    2. Re:In case you missed it by busyqth · · Score: 5, Insightful

      Hmm... "my fox tampa bay" and "bob owens"... two totally trustworthy news sites there. good job.

    3. Re:In case you missed it by TheRealGrogan · · Score: 5, Insightful

      It doesn't even matter if he was beaten... he should be.. We don't have to recognize the authority of Neighbourhood Watch snitches. If they think there is an issue, they are to call the police. That's it. If they engage, WE have the right to self defense. They don't have police powers and if they attempt to bar my egress I won't hesitate to use as much force as necessary.

    4. Re:In case you missed it by tomhath · · Score: 5, Interesting

      Note that the video was taken well *after* EMTs had treated him at the scene. I wouldn't expect video of that quality to show anything at that point. While it would be interesting to hear what the EMTs saw, if they say he appeared to have been beaten you won't believe them.

    5. Re:In case you missed it by mc6809e · · Score: 5, Interesting

      Having seen the full video, I can come to only one conclusion: the video does not show any solid evidence of injuries because the quality is low. I saw some things that may have been injuries, but they could have just as easily been due to the shape of his head.

      By the way, Sanford has put up the videos and 911 calls at http://sanfordfl.gov/investigation/trayvon_martin.html

      Interesting thing about the video is that the original source looks like it was recorded on videotape as interlaced NTSC! You can see this when there's a great deal of movement going on. Just look for areas of great contrast like the hood of the police car when it rolls in and you'll notice the odd saw-tooth appearance of the hood's edge. This happens in other places.

      What this means is that a lot of what is being seen is what has been filled in by software as it deals with crappy NTSC. Noise, color fringing effects, are all smoothed out. Then lossy compression is used during the conversion to digital video and potentiall important detail is lost.

      The result is that the video appears better than it really is.

      This is what most people want when they're transferring analog video to digital. But here is it's absolutely essential that we see the raw, unaltered video, if for no other reason than for understanding the limits of equipment used. It possible the equipment just wasn't good enough to pick up the details we're looking for.

    6. Re:In case you missed it by Mitreya · · Score: 5, Insightful

      While it would be interesting to hear what the EMTs saw, if they say he appeared to have been beaten you won't believe them.

      I would totally believe the EMTs if they testified to that under oath in court. Of course I wouldn't really believe Zimmerman's claims, since he obviously has a bit of a bias
      Problem is, he's not had to defend himself in court, to bring all that exonerating evidence. Police just took his word for it.

    7. Re:In case you missed it by frank249 · · Score: 5, Insightful

      If the EMTs treated Zimmerman, then they would have put a dressing over any break in the skin to prevent infection. The back of his head does not even have a band aid on it. If he had a broken nose there would have been blood on his shirt and jacket and you would likely see nose plugs to stop the bleeding. There also would have been swelling. No evidence of this either.

      --

      Today's vices may be tomorrow's virtues.

    8. Re:In case you missed it by Anonymous Coward · · Score: 5, Informative

      Hmm... "my fox tampa bay" and "bob owens"... two totally trustworthy news sites there. good job.

      When NBC News played the audio of the 911 call George Zimmerman made prior to the confrontation that resulted in the death Travyon Martin, this is what they played:

              Zimmerman: This guy looks like he's up to no good. He looks black.

      That audio helped fan the nation-wide flames of hysteria over the supposed fact that the police had released an obvious racist who had tracked and killed Martin out of racist motives. Many Republicans, such as Jeb Bush, the highly regarded former governor of Florida, and many "conservatives," such as Rich Lowry, the editor of America's flagship "conservative" magazine, believed it.

      But the audio played by NBC, though it seemed like "fact" (because it was an audio, and isn't audio true?) was false.

      Here is the transcript of the actual audio of the 911 call:

              Zimmerman: This guy looks like he's up to no good. Or he's on drugs or something. It's raining and he's just walking around, looking about.

              Dispatcher: OK, and this guy--is he black, white or Hispanic?

              Zimmerman: He looks black.

      That is the slipshod hoodwinking professional reporting we need then?

    9. Re:In case you missed it by realityimpaired · · Score: 5, Insightful

      I wasn't there, so I have no real opinion on the whole thing other than to say, "I do hope they figure out what really happened so we can put it all to rest." There are important, unanswered questions about what happened and both theories seem entirely plausible to me.

      The 911 calls clearly show that Zimmerman pursued Martin after having been told not to, and Martin was found to have had no weapons of any kind on his person. Neither of those facts have been disputed by any version of events that I've heard. Where's the doubt and unanswered questions for you?

      Quite honestly, it doesn't matter if Martin beat the crap out of Zimmerman before he was shot. Zimmerman was an armed man following him as he was trying to go about his daily business. In the same situation, I would have done the same. *that* is the self defense in this situation. If there was an altercation before Martin was shot, it was because Martin was trying to defend himself against Zimmerman. It's not relevant to the fact that Zimmerman followed him after having been told not to, and that as a direct result of that, Martin was killed. Whether it's manslaughter or premeditated may be in question, but there should be no doubt at all that Martin was murdered.

      While I don't like turning this into a racial thing, the unfortunate reality is that if Martin was a 17-year old white girl, there wouldn't be any doubt whether Zimmerman was a murderer. Unfortunately, his victim was a 17-year old black boy. That, alone, is enough in the minds of some people to cast doubt on whether it was murder or self defense, and it makes me sick to my stomach. That kid did not have to die, and he is being denied justice by a police force that refuses to arrest and charge his killer.

      Unfortunately, the racial tensions that are coming out of the woodwork over this one are exactly the reason that Martin was killed in the first place: in the US, the schism between Blacks and Whites was never resolved. It was put on the back burner and allowed to fester while on the surface people pretended it was done with. As long as there continues to exist a double standard, it can never be resolved properly.

      The US is not alone in this... there's similar problems in other countries... look at how France is treating the Muslims (well, the US is doing it, too). Look at how "witches" are being treated in Africa and India. Look at how the first nations population is grossly over-represented in Canadian prisons. The world has a lot of problems. My only hope (aside from justice for Martin) is that it will open a dialogue and people will realise that the colour of your skin is not an indicator of what you will do with your life. Sadly, I think that realisation is generations away in parts of the US. (and yes, it took generations in other parts of the world, but we had a head start... in the British Empire, for example, slavery was officially abolished in 1833, but was largely gone already by 1797 and had been ruled in 1772 that Slavery was not legal in England itself, only the colonies... the beginnings of desegregation in England go back to a 1569 report, which declared that "England [was] too pure an air for a slave to breathe in". So we've had a bit of a head start.)

    10. Re:In case you missed it by jo_ham · · Score: 5, Informative

      Well, Fox did go to court to defend the right to lie in "news" stories. Take anything you read or hear from Fox with a *massive* grain of salt.

  2. Re:April Fools by ohnocitizen · · Score: 5, Insightful

    Really? Slashdot has frequent coverage of human rights, crime, law enforcement. Technology alone isn't the only subject Slashdot readers are interested in. It just so happens that technology and forensics do play a role in this story. However even if they didn't, this is a huge story, and well worth covering on Slashdot.

  3. Science or Pseudo-science? by Jazari · · Score: 5, Interesting

    Has this software been subjected to repeated double-blind testing? Otherwise, there's no point in reporting this.

  4. Does This Tool Actually Work? by Stormy+Dragon · · Score: 5, Insightful

    While I'm personally of the opinion that Zimmerman is guilty of manslaughter, I've also seen too many cases of "forensic science" of dubious validity being allowed in trials (for example Steven Hayne in Mississippi help convict dozens of people on the base of 'bite mark identification' techniques that are widely considered fraudulent). Can anyone point to any independent blind trials to demonstrate 1) that the metrics used by this program actually are invariant for a particular individual and 2) are sufficiently unique that they can be used to reliably distinguish two individuals?

    1. Re:Does This Tool Actually Work? by gstrickler · · Score: 5, Insightful

      Yes, but there are so many holes in his story that it's beyond belief. There is no question of who shot Trayvon, Zimmerman has admitted that. He's claiming self-defense, and his story doesn't hold up to any scrutiny. He should be (should have already been) arrested and charged, and let the legal system handle it, not the media and public outcry. If they don't have enough evidence, then the grand jury can refuse to indict. If they do, then he goes to trial or makes a plea.

      --
      make imaginary.friends COUNT=100 VISIBLE=false
    2. Re:Does This Tool Actually Work? by Dan+East · · Score: 5, Interesting

      I think there's a significant problem in the way this software is being used in this case. It is one thing to say that, based on samples of an individual's voice, that there is X probability that some other voice sample could be from the same person. However, there isn't any way the software can do the opposite and prove a negative. For example, you can take hours of recordings of my voice from phone conversations and train the software. Now, if I make my voice sound like Donald Duck, or if I sing in falsetto, which are two types of sounds that would not be in the sampling of my normal voice, what probability would the software return that the silly voice matches my normal voice? It would be very low, at is should be.

      In this case we have a sample of someone's NOT NORMAL VOICE. They are screaming and yelling. What voice samples of Zimmerman's were used to train the software? Was it recordings of him screaming and yelling? If not then of course the software will return a low probability. Actually, I'm surprised it returned as high of a probability as it did.

      Now, as a side note, I think the news is really trying to inflame this whole deal. I think Zimmerman is likely in the wrong here, however, the media is running rampant with speculation. A good example are the video clips of Zimmerman at the police station, and them (news media) saying it doesn't look like his nose is broken, or that there doesn't appear to be blood all over him. That sort of thing is completely impossible to determine from the crappy, low resolution security video. Again, yes, if there was that much blood and it could be seen in the video, then a positive could be "proven", but just because it doesn't show up in the video doesn't mean he has significant injuries or a broken nose, etc.

      --
      Better known as 318230.
    3. Re:Does This Tool Actually Work? by sjames · · Score: 5, Insightful

      That's exactly it. We know for a fact that he began from a position of safety (since he was on the phone w/ 911). Stand your ground does not mean charge into danger. We know the victim had no weapon. That makes the threat to life or grievous bodily harm seem unlikely. It really does seem like more than enough to justify deeper investigation, but instead the DA has already delivered a poor excuse for no charges which generally indicates there will be none..

    4. Re:Does This Tool Actually Work? by Anonymous Coward · · Score: 5, Interesting

      This reminds me of the infamous plane identification software. Its accuracy got up to 100%. They were so happy that they managed to do it. Put it out in the field and there were all sorts of false positives and false negatives. Turns out that the software got so good at guessing because with the test photos, all the good planes were shot against bright blue sky and the bad planes were shot against dark sky. The software made all its predictions based on the sky color.

    5. Re:Does This Tool Actually Work? by gstrickler · · Score: 5, Interesting

      Voice analysis is a well established and studied technique. Unless you're particularly practiced and adept at disguising your voice, there are certain characteristics introduced by the physics of your vocal cords, throat, mouth, and nasal passages that are pretty consistent and identifiable, even with most people doing "impersonations" that sound like some other person. So, yes, it's reasonable to rule out that it was Zimmerman, in fact, it's more reliable at excluding people than at matching them. As Mr Owen points out, this recording has low background noise levels, and it's got a notable amount of Zimmerman's speech recorded in addition to the screams for help, so there is no issue introduced by aging, colds, etc. It's a nearly ideal case for matching.

      --
      make imaginary.friends COUNT=100 VISIBLE=false
    6. Re:Does This Tool Actually Work? by Tyler+Durden · · Score: 5, Interesting

      Treyvon was a young 6' 3" muscular basketball player

      I'm undecided on wether Zimmerman is guilty or not without seeing further evidence myself. But it would be a stretch to call Trayvon "muscular". Kid weighed 140 pounds at 6' 3". I weigh that at 5' 7" and people think I'm too thin. He was a beanpole.

      --
      Happy people make bad consumers.
    7. Re:Does This Tool Actually Work? by bieber · · Score: 5, Informative
      Have you read anything about the case?

      Being on the phone does not magically make one safe.

      No, but being on the phone in a vehicle, someone who neither knows nor cares that you exist is not a threat.

      Did Zimmernan at the time?

      Yes, he was carrying a gun; what do you think he shot Trayvon with? He chose to leave the safety of his vehicle to pursue an unarmed teenager while carrying. He then provoked a confrontation by, you know, chasing down an unarmed kid. None of these facts are challenged by Zimmerman or the police. At this point, whether Trayvon threw the first punch isn't terribly important. He had every right to feel threatened if Zimmerman was pursuing him, especially if he noticed the gun, and to defend himself from that threat. You can't just provoke a fight and then invoke self-defense when the person defending themselves from you gets the upper hand.

    8. Re:Does This Tool Actually Work? by gstrickler · · Score: 5, Insightful

      Exactly. Zimmerman followed Trayvon despite being told not to, got out of his car, armed with a gun and started a confrontation, then shot Trayvon, that's not self-defense, and it's not covered under Florida's "Stand your ground" statute as far as I can tell. It needs to be put before a jury to determine if he's guilty, so he definitely needs to be arrested and charged and let the legal system work it out.

      --
      make imaginary.friends COUNT=100 VISIBLE=false
  5. Re:So what? by Tenebrousedge · · Score: 5, Insightful

    I'm more concerned that someone under the presumption of innocence is instead being tried in the court of public opinion, which obeys no law and follows no procedure. Regardless of the facts of the matter, I would almost rather have my day in court and be acquitted than have my life torn to pieces in a three-ring media circus.

    --
    Those who advocate genocide deserve every protection afforded by law, and none afforded by common human decency.
  6. Re:Slashdot by busyqth · · Score: 5, Insightful

    all the actual techies have left and been replaced with libertarian trolls.

    Huh? I remember way back when quoting Ayn Rand on Slashdot was a sure ticket to +5 Insightful. And you say that Slashdot is infested with libertarian trolls now?

  7. Re:So what? by Anonymous Coward · · Score: 5, Insightful

    If only the guy who shot another person without witnesses would have been actually *investigated*, instead of letting him walk entirely on his own testimony...

  8. Re:So what? by Cwix · · Score: 5, Insightful

    I agree, he shouldn't be facing the court of public opinion. He should be facing the court of law. It certainly doesn't look like that is happening.

    --
    You are entitled to your own opinions, not your own facts.
  9. It's not a question of innocence by meosborne · · Score: 5, Insightful

    It's not a question of guilt or innocence, Zimmerman is guilty of shooting and killing Trayvon Martin. That is not in question at all. The question is whether he was legally justified in doing so. Unfortunately, one side of the story (Trayvon) has been removed and cannot be heard.

    A human being *died*. A young man was shot and killed while bearing only a can of iced tea and a bag of skittles. An investigation of more than simply accepting the word of the shooter is definitely warranted.

  10. yawn: "trial by rumor" by peter303 · · Score: 5, Insightful

    "Trial by social media". "Trial by the self-righteous" Glad we have court systems to sort out all these rumors.

    1. Re:yawn: "trial by rumor" by BasilBrush · · Score: 5, Insightful

      If only the court system was being used.

  11. Re:So what? by Wrath0fb0b · · Score: 5, Informative

    I agree, he shouldn't be facing the court of public opinion. He should be facing the court of law. It certainly doesn't look like that is happening.

    It looks increasingly likely that he will face a jury. And when he does, the jury will likely be informed of Fla. Stats. 776.041, which states:

    776.041âfUse of force by aggressor.â"The justification [of self defense] described in the preceding sections of this chapter is not available to a person who:
    (1)âfIs attempting to commit, committing, or escaping after the commission of, a forcible felony; or
    (2)âfInitially provokes the use of force against himself or herself, unless:
    (a)âfSuch force is so great that the person reasonably believes that he or she is in imminent danger of death or great bodily harm and that he or she has exhausted every reasonable means to escape such danger other than the use of force which is likely to cause death or great bodily harm to the assailant; or
    (b)âfIn good faith, the person withdraws from physical contact with the assailant and indicates clearly to the assailant that he or she desires to withdraw and terminate the use of force, but the assailant continues or resumes the use of force.

    To be brutally honest, I think both his attackers and his defenders sound very silly to me in making bold statements before the facts are in. The prudent thing to do is to simply say that we are not going to condemn him or exonerate him until the process plays out and renders a verdict.

    [ Note, I'm not saying that everyone must accept the results of the process -- just because it's the legal result doesn't mean we have to personally believe it. But there is a difference between disagreeing with the result after it happens and jumping to your own conclusion before it has been conducted. The former seems to me reasonable, the latter not so much. ]

  12. Re:So what? by Troyusrex · · Score: 5, Insightful

    There aren't "well established facts" in this case. At least not that are known to the general public. Cases tried in the media tend to be enormously biased because they are about generating interest not about reliable evidence. For instance, was Zimmerman's nose broken and the back of his head injured or not? We don't know but such evidence would obviously make a big difference in the case.

  13. Re:So what? by Mistlefoot · · Score: 5, Insightful

    I agree.

    Is it self defence if I am breaking into someone's else home, they grab a knife and "attack" me and I shoot them as I fear for my life?
    Clearly no. The homeowner has the right to defend themselves from the instigator.

    Is it self defence if I stalk someone walking down the road and they "attack" me and I shoot them as I fear for my life?
    Or let's ask it backwards.
    If I am walking down the street minding my own business and I am followed and stalked by another are they allowed to kill me when I defend myself?
    EVEN if Zimmerman found himself defending himself he should still be investigated as evidence indicates that he is defending himself from an event he initiated.

    Trayvon, per mobile conversation with his girlfriend:

    ""He says: 'Oh, he's right behind me. He's right behind me again,'" Crump said the girl told him. "She says: 'Run.' He says: 'I'm not going to run, I'm just going to walk fast.'

    She then heard Martin saying "Why are you following me""

    Florida stalking law arguably shows that Trayvon was being stalked. Easily as arguable as the "stand your ground" arguement. And that would mean that he was killed by someone in the commision of a crime.

    "FLORIDA

    Section 784.048. STALKING; DEFINITIONS; PENALTIES. 1997.

    (1) As used in this section, the term:

    (a) "Harass" means to engage in a course of conduct directed at a specific person that causes substantial emotional distress in such person and serves no legitimate purpose.

    (b) "Course of conduct" means a pattern a conduct composed of series of acts over a period of time, however short, evidencing a continuity of purpose. Constitutionally protected activity is not included within the meaning of "course of conduct." Such constitutionally protected activity includes picketing or other organized protests.

    (c) "Credible threat" means a threat made with the intent to cause the person who is the target of the threat to reasonably fear for his or her safety. The threat must be against the life of, or a threat to cause bodily injury to, a person."

  14. Re:So what? by misexistentialist · · Score: 5, Insightful

    None of those three items are laws, the breaking of which would be chargeable offenses. Carrying the gun was legal, as was observing someone in public (or a private neighborhood which Zimmerman was responsible for securing). If Martin attacked him, he was the first and only person who broke a law.

  15. Re:So what? by shutdown+-p+now · · Score: 5, Informative

    You do know that there was at least one eyewitness that corroborated that Zimmerman was on the ground being attacked and calling for help?

    You do know there are other eyewitnesses who claimed that was not the case? That's your probable cause right there.

  16. Re:So what? by mikelieman · · Score: 5, Insightful

    Not really. There's 2 essential elements to charging manslaughter in Florida, and Zimmerman meets them.

    They are, (1) Trayvon Martin is dead and (2) George Zimmerman killed him.

    I don't give a shit about anything else. Zimmerman can tell his story to a Judge, and if the Judge buys his motion to dismiss, then so be it.

    --
    Technology -- No Place For Wimps! Grateful Dead and Jerry Garcia Chatroom -- http://www.wemissjerry.org
  17. Re:So what? by cold+fjord · · Score: 5, Informative

    You do know there are other eyewitnesses who claimed that was not the case? That's your probable cause right there.

    Fabulous! New information! I'm for new information. Here is a link showing the eye witness I'm referring to:

    In addition, an eyewitness, 13-year-old Austin Brown, told police he saw a man fitting Zimmerman's description lying on the grass moaning and crying for help just seconds before he heard the gunshot that killed Martin.

    And here is another report, which seems consistent with the above, and seems to be someone different:

    After hearing raised voice, the witness said he peered out of the window and saw two men grappling with each other on the ground, one on top of the other. He said there were two struggles, both of which were on the grass next to a sidewalk. “I heard the yell for help then I heard another as I would describe as an excruciating type of yell. It didn’t even sound like a help it just sounded so painful,” he said. Following the cry, he described hearing “popping” sounds, believed to be multiple gunshots. One of the men then cried out for help.

    And of course Zimmerman was treated on the scene for head injuries, which is again consistent with the other reports.

    As it was, the police took Zimmerman in for questioning in handcuffs, and released him. They know where he lives.

    Do you have a link for me?

    --
    much of left-wing thought is a kind of playing with fire by people who don't even know that fire is hot - George Orwell
  18. Re:So what? by SockPuppetOfTheWeek · · Score: 5, Insightful

    You know what? I'm not playing this game.

    There is no such thing as "injuries severe enough to justify lethal force". If someone has reasonable cause to fear for their safety, if you injure them at all, they are justified in using any and all available force to stop you from injuring them further. Period.

    Don't like it? Don't start fights you can't win. And since concealed carry is legal (and Zimmerman had a CCW permit, by the way), you have no way of knowing whether someone has a concealed weapon. So, the moral of the story: don't start fights.

  19. Re:So what? by mohhomad · · Score: 5, Informative

    Except he wouldn't have broken the law if he believed he was protecting himself. The beauty of the Florida stand your ground law is that it's so broad that had Martin killed Zimmerman he could have plead self defense. Except for the fact that he was black and not the son of a judge. Florida's stand your ground law protects the instigator. That's the point of stand your ground laws. Prior to SYG the standard was that you had to try and avoid or escape situations that require deadly force. Florida's statue is so broad that believing you are preventing a felony is a good enough reason to shoot to kill.

  20. Re:What difference does it make? by jamesh · · Score: 5, Insightful

    A 911 dispatcher is NOT a cop and has NO authority. Being told to leave the kid alone by the 911 operator means nothing in any legal sense.

    Nobody is saying the 911 dispatcher has any legal authority. It was advice. Good advice. If he had followed that advice and stayed where he was we mightn't be in this mess now. At the very least there wouldn't be the public opinion that he put himself in a position where using his gun might be considered even remotely necessary.

    Just because "you're not the boss of me" doesn't mean you shouldn't listen to the person offering the advice.

  21. Re:So what? by manwargi · · Score: 5, Interesting

    In 2009 there were 2,867 black males killed in the United States, of which 2,604 were killed by other blacks, 209 killed by whites. Why the outrage in this case? Might it be various people made assumptions about how this would play out?

    It might, might, might just have something to do with the fact that this was not such a cut and dry scenario, and the suspect wasn't arrested. Of those 2,867 killings you cite, how many of those killers were arrested for murder or manslaughter? How many of those cases were regarded as self-defense?

    People are understandably quick to bring race into the equation, but on it's most underlying level, an unarmed boy was shot by a large adult with a gun and an arrest wasn't made. The unarmed boy was reportedly making a run for junk food for his younger brother, the armed man was at some point following the boy around after being advised not to because the police were on the way. It's suspicious, regardless of what color either character is.