233 F.3d 514 (7th Cir. 2000)
J.H. Desnick, M.D., Eye Services, Ltd., Plaintiff-Appellant,v.American Broadcasting Companies, Inc.,  Jon Entine, and Sam Donaldson, Defendants-Appellees.
No. 99-3715
In the  United States Court of Appeals  For the Seventh Circuit
Argued September 12, 2000Decided October 27, 2000

Appeal from the United States District Court  for the Northern District of Illinois, Eastern Division.  No. 93 C 6534--John A. Nordberg, Judge.[Copyrighted Material Omitted]
Before Posner, Coffey, and Manion, Circuit Judges.
Posner, Circuit Judge.


1
Seven years ago the  Desnick eye clinic, joined by two of the clinic's  surgeons (who are no longer parties), brought  this diversity suit against the ABC television  network, a producer of ABC's program "PrimeTime  Live," and the program's star reporter, Sam  Donaldson, seeking damages for a variety of torts  allegedly committed by the defendants in  connection with a 15-minute program segment that  was highly critical of the clinic. We affirmed  the district court's dismissal, on the ground of  failure to state a claim (Fed. R. Civ. P.  12(b)(6)), of all but the defamation charge. 44  F.3d 1345 (7th Cir. 1995). That charge was based  on an accusation in the broadcast that the  plaintiffs had tampered with a machine at the  clinic called an "auto-refractor," which tests  for cataract. The district judge had dismissed  the charge on the ground that the accusation had  not added significantly to the harm to the  plaintiffs' reputation caused by the parts of the  broadcast segment that the plaintiffs had not  challenged. We reversed because the fact that the  plaintiffs had not challenged the other  accusations in the broadcast could not be  construed as a concession that those other  accusations were true. Id. at 1350-51. "Given the  obstacles to proving defamation, the failure to  mount a legal challenge to a defamatory statement  cannot be considered an admission that the  statement is true." Id. at 1350. On remand, the  district court granted summary judgment for the  defendants, without reaching the question whether  the accusation of tampering was true or false, on  the ground that there was insufficient evidence  of "actual malice" to permit the case to go  forward. The Desnick clinic has again appealed.


2
The clinic is conceded to be a "public figure,"  so that under the Supreme Court's interpretation  of the free-speech clause of the First Amendment  it cannot maintain a suit for defamation unless  it can prove that the defendant acted with  "actual malice." This is a term of legal art that  means not what it seems to mean but that the  defendant either knew that the defamatory  statement (here, the accusation of tampering with  the auto-refractor) was false or was recklessly  indifferent to whether it was true or false.  E.g., Masson v. New Yorker Magazine, Inc., 501  U.S. 496, 510 (1991); Milsap v. Journal/Sentinel  Inc., 100 F.3d 1265, 1270 (7th Cir. 1996) (per  curiam). "Reckless indifference" denotes the same  state of mind that must be proved to establish  liability for infringement of a federal right  under color of state law or for violation of the  federal mail fraud statute knowledge by the  defendant that there was a high risk of harm to  the plaintiff coupled with a failure to take any  feasible measure to counter the risk, either by  investigating further to see whether there really  is a risk and how serious it is or by desisting  from the risky activity. See, e.g., Farmer v.  Brennan, 511 U.S. 825, 837-38 (1994); Tesch v.  County of Green Lake, 157 F.3d 465, 474-75 (7th  Cir. 1998); Billman v. Indiana Dept. of  Corrections, 56 F.3d 785, 788-89 (7th Cir. 1995);  Archie v. City of Racine, 847 F.2d 1211, 1219  (7th Cir. 1988) (en banc); United States v. Dick,  744 F.2d 546, 551 (7th Cir. 1984); Chance v.  Armstrong, 143 F.3d 698, 703-04 (2d Cir. 1998);  United States v. DeSantis, 134 F.3d 760, 764 (6th  Cir. 1998); Keeper v. King, 130 F.3d 1309, 1314  (8th Cir. 1997).


3
In a defamation case by a public figure,  therefore, "the plaintiff must demonstrate that  the author 'in fact entertained serious doubts as  to the truth of his publication,' . . . or acted  with a 'high degree of awareness of . . .  probable falsity,'" Masson v. New Yorker  Magazine, supra, 501 U.S. at 510 (quoting St.  Amant v. Thompson, 390 U.S. 727, 731 (1968), and  Garrison v. Louisiana, 379 U.S. 64, 74 (1964),  respectively), or, while suspecting falsity,  deliberately avoided taking steps that would have  confirmed the suspicion. Harte-Hanks  Communications, Inc. v. Connaughton, 491 U.S.  657, 692-93 (1989) ("intent to avoid the truth,"  id. at 693); Eastwood v. National Enquirer, Inc.,  123 F.3d 1249, 1251 (9th Cir. 1997); McFarlane v.  Sheridan Square Press, Inc., 91 F.3d 1501, 1510  (D.C. Cir. 1996). (For the analog to this  "ostrich" or "willful blindness" principle in  cases under 42 U.S.C. sec. 1983, see West v.  Waymire, 114 F.3d 646, 651 (7th Cir. 1997).) In  other words, the defendant must either know that  his published statement was probably false or,  suspecting that it may be false, deliberately  close his eyes to the possibility.


4
This is the criminal sense of recklessness,  Farmer v. Brennan, supra, 511 U.S. at 839-40;  Hill v. Shobe, 93 F.3d 418, 421 (7th Cir. 1996);  Hemmings v. Gorczyk, 134 F.3d 104, 108 (2d Cir.  1998) (per curiam), or, if a little broader, is  so only by a hair, West v. Waymire, supra, 114  F.3d at 650-52, whereas in tort cases the term  sometimes denotes little more than gross  negligence. Farmer v. Brennan, supra, 511 U.S. at  836 n. 4; Duckworth v. Franzen, 780 F.2d 645, 652  (7th Cir. 1985); In re New York City Asbestos  Litigation, 678 N.E.2d 467 (N.Y. 1997) (per  curiam); W. Page Keeton et al., Prosser and  Keeton on the Law of Torts sec. 34, p. 213-14  (5th ed. 1984). Negligence, the standard in  defamation suits brought by private rather than  public figures, does not require proof of a state  of mind at all, but only that the defendant  failed to exercise the care that a reasonable  person in his position would have exercised. The  contrast with recklessness in the strong sense in  which the term is used to denote the standard in  constitutional, mail-fraud, and public-figure  defamation cases is stark. "Reckless conduct [in  a public-figure defamation case] is not measured  by whether a reasonably prudent man would have  published, or would have investigated before  publishing. There must be sufficient evidence to  permit the conclusion that the defendant in fact  entertained serious doubts as to the truth of his  publication. Publishing with such doubts shows  reckless disregard for truth or falsity and  demonstrates actual malice." St. Amant v.  Thompson, supra, 390 U.S. at 731. We may assume  that the defendants were careless in having  failed to investigate the auto-refractor  accusation further; but there is no evidence that  they actually believed the accusation to be false  and so the question is whether the clinic has  presented enough evidence of recklessness to  defeat summary judgment.


5
The accusation of tampering was made originally  by Paddy Kalish, an optometrist who had worked  for the Desnick eye clinic for two years. Kalish  claimed that technicians employed by the clinic  tampered (at the clinic's direction) with the  auto-refractor in order to produce false  diagnoses of cataract. A symptom of cataract is  that one's normal eyesight becomes severely  degraded when there is a lot of glare. The auto-  refractor tests for this symptom as follows.  First it inspects the patient's eyes without  glare. The machine automatically adjusts for  whatever correction the patient requires, so that  if the patient's vision has been corrected to  20/20 that is what the eye chart in the machine  will report. Then the glare function is  activated. If the patient does not have a  cataract, his vision will still register as  20/20, but if he does have a cataract, the glare  will degrade his vision, and if it degrades it to  20/50 or worse this is an indication that he  needs surgery to remove the cataract. According  to Kalish, the glare created by the machine can  be amplified to degrade the patient's vision even  if the patient does not have a cataract. In an  interview with Donaldson that was videotaped  (only part of which was used in the broadcast),  Kalish first tested Donaldson to ascertain that  without tampering his corrected vision was 20/20  even with the glare produced by the (untampered-  with) machine. In other words, Donaldson did not  have a cataract. Then Kalish explained that the  glare could be intensified by removing the  housing of a part of the machine and unscrewing  the "glare bulb" exposed by that removal,  covering the bulb with a piece of scotch tape,  "painting" the tape with a magic marker, and  reinstalling the bulb. The dimming of this bulb  caused by the tampering is detected by a glare  detector in the machine, and the glare detector  reacts by sending more power to the glare bulb,  and Kalish said that the net effect is to create  increased glare in the patient's field of vision.  After several failed attempts to degrade  Donaldson's vision, Kalish with the aid of a  friend of his, a technician formerly employed by  him, was able to degrade Donaldson's vision to  20/40.


6
There is nothing, so far, to indicate any  recklessness on the part of ABC in crediting  Kalish's accusation. It is true that Kalish and  the technician needed several attempts to degrade  Donaldson's vision, but this is not surprising or  suspicious. The machine was new to the  technician, and Kalish had not done the tampering  of the eye clinic's machine himself. Nor is it  significant that Donaldson's vision was not  degraded to the 20/50 level, given the  technician's lack of tampering experience and the  fact that Donaldson was younger than the patients  at the clinic, almost all of whom were Medicare-  eligible and thus 65 or older. The technique of  tampering was odd--dimming the glare bulb in  order to signal the glare detector to restore its  brightness doesn't seem a likely recipe for a net  increase in glare. The obvious way to achieve  this end would be to mask the detector, causing  it to send additional power to the undimmed glare  bulb. The manufacturer of the auto-refractor  acknowledged that the machine could be caused to  register false positives in this way, and it is  likely that Kalish, who had not done the actual  tampering himself but merely observed it,  mistakenly thought that the tamperer covered the  bulb rather than the detector, which sits beside  it in the machine.


7
The accusation of tampering was corroborated by  the fact that ABC's investigation of the Desnick  clinic turned up evidence of unneeded surgery,  alteration of patients' records to show they  needed cataract surgery when they didn't,  diagnoses by clinic surgeons of cataract in  testers (ABC "undercover agents") with normal  eyesight, and statements by former employees of  the clinic that almost everyone failed the glare  test. The plaintiff points out correctly that  these "facts" have not yet been established,  because the district judge dismissed the suit  before determining their truth. But that is  irrelevant. All that matters is that ABC was not  reckless in stating these as facts, facts  establishing a pattern of herding elderly  patients into unneeded cataract surgery, or in  making the further charge that a diagnostic  machine had been tampered with to produce false  positives.


8
The defendants knew more than the facts we have  summarized so far, however, and it is on the  "more" that the plaintiff pitches its contention  that a jury could infer that they knew there was  a high probability that Kalish's accusation, at  least, was false. But neither singly nor in  combination do the additional facts that the  defendants knew permit such an inference.


9
One thing they knew was that the U.S. Attorney  had refused to join Kalish's multimillion  whistleblower dollar suit against the clinic (a  suit that ultimately failed, though for a reason  unrelated to Kalish's credibility--that he lacked  standing to bring such a suit) because he didn't  think that Kalish could be the centerpiece of a  credible suit. But he didn't think that because  he thought Kalish was lying but because he  thought Kalish might not be believed, having  worked for the clinic for two years and during  his employment having participated in the  clinic's unethical practices. That Kalish might  not be credible enough to have a good chance of  persuading a jury does not mean that he was not  credible enough to be a source for a news story.  Many a criminal conviction has rested entirely on  the testimony of coconspirators despite the  requirement in a criminal case of proof beyond a  reasonable doubt; a fortiori a broadcaster is  entitled to repose confidence in a conspirator  unless the circumstances create in the  broadcaster's mind a belief that there is a high  probability that the conspirator is lying.


10
The plaintiff in its brief repeatedly urges us  to view the "outtakes" of Donaldson's interview  of Kalish, that is, the parts of the videotape  that were not broadcast; and we have done so. The  plaintiff directs us to Donaldson's statement in  the outtakes that "this is silly." But the  referent is omitted. In one of the failed  attempts to rig the machine, the piece of scotch  tape was left wedged in it and Kalish suggested  that he darken the bulb with the magic marker and  then reinsert it. Evidently what Donaldson  thought "silly" was attempting to rig the machine  in two stages. The fact revealed by the outtakes  and much harped on by the plaintiff that Kalish  and the technician needed repeated attempts to  tamper with the machine successfully has no  significance given that the technician was not as  knowledgeable about the machine as a Desnick eye  clinic technician would have been. Incidentally,  the fact that Kalish couldn't do the tampering  himself, that he is clumsy and needed the assistance of a technician, has a significance  unrecognized by the plaintiff. Given his lack of  mechanical aptitude, it is unlikely that Kalish  could have made up this method of tampering had  he never seen or heard about it, though as we  noted earlier he may have been confused as the  precise method of tampering that he had observed.  The clinic's lawyer speculated at the oral  argument of the appeal that maybe Kalish had  heard about the method of tampering from someone  unrelated to Desnick's clinic. Maybe. But it was  not a possibility that ABC was required to  entertain seriously, given all the evidence it  had that was corroborative of Kalish's  accusation.


11
The plaintiff points out that ABC did not  attempt to hunt up the actual technicians  employed by the plaintiff who had tampered with  the machine. This is true, and maybe that failure  was negligent, though it is understandable why  ABC might think it an unprofitable quest people are reluctant to admit their misconduct. But  negligence is not the applicable standard.


12
Potentially the best fact for the plaintiff is  that, as the defendants well knew (because the  plaintiff's lawyer told them), the clinic had  sued Kalish in state court on account of the  tampering accusation, which Kalish had made on a  local television station before the "PrimeTime  Live" broadcast, and had won a judgment. The  plaintiff argues that the judgment "necessarily  encompassed a finding that Kalish had made false  statements about Dr. Desnick," but that is  incorrect; summary judgment was granted for the  plaintiff after Kalish's lawyer failed to make a  timely response to a request for admissions.  Still, the fact that Kalish had lost a defamation  suit based on the identical accusation should  have set off warning bells at ABC; and it is  conceivable (though we need not decide) that the  failure to follow up was reckless, was a case of  "intent not to learn the truth." There is  nevertheless a fatal flaw in this part of the  plaintiff's case: the plaintiff's failure to  indicate what following up would have revealed.  It is not enough to argue that ABC should have  examined the state court record. The plaintiff  must show what the record contained that would  bear on Kalish's credibility. True, this  principle is assumed rather than stated in the  cases. See McFarlane v. Sheridan Square Press,  Inc., supra, 91 F.3d at 1510; Brown v. Hearst  Corp., 54 F.3d 21, 26 (1st Cir. 1995); Perk v.  Readers Digest Association, Inc., 931 F.2d 408,  412 (6th Cir. 1991). But there is a compelling  analogy to the duty of a party who complains  about the exclusion of testimony to show by an  offer of proof that the testimony would have been  helpful. Fed. R. Evid. 103(a)(2); United States  v. Vest, 116 F.3d 1179, 1189 (7th Cir. 1997);  Israel Travel Advisor Service v. Israel Identity  Tours, 61 F.3d 1250, 1260 (7th Cir. 1995); Faigin  v. Kelly, 184 F.3d 67, 86 (1st Cir. 1999).


13
Suppose that all that a study of the record in  the clinic's suit against Kalish would have  revealed was a procedural bobble on the part of  Kalish's lawyer. It would not be surprising if  the suit had not been defended vigorously, for  Kalish appears to be a person of modest means and  it is entirely possible that the clinic sued him  not in the hope of obtaining a collectible  judgment but in the hope of silencing him and  destroying his credibility. This is speculation;  our point is different--it is that without any  indication that ABC would have learned that  Kalish's accusations were false had it studied  the record of the clinic's suit against him,  there is no evidence of a causal relation between  ABC's alleged recklessness and the injury to the  clinic. So far as appears, a study of the record  would have brought to light nothing that would  have cast any doubt on Kalish's truthfulness. The  only aspect of the defendants' conduct that might  be considered reckless was also, so far as the  record discloses, harmless. Cf. Franks v. Delaware, 438 U.S. 154, 171-72 (1978).


14
Affirmed.

