NONPRECEDENTIAL DISPOSITION
                       To be cited only in accordance with Fed. R. App. P. 32.1




                   United States Court of Appeals
                                   For the Seventh Circuit
                                   Chicago, Illinois 60604
                                Argued September 24, 2018
                                Decided September 27, 2018



                                            Before

                          DIANE P. WOOD, Chief Judge

                          FRANK H. EASTERBROOK, Circuit Judge

                          MICHAEL B. BRENNAN, Circuit Judge



No. 18-1204                                                   Appeal from the United
                                                              States District Court for the
JOSHUA MILLIGAN, by his legal guardian and                    Western District of Wiscon-
conservator Susan Thomas,
                                                              sin.
      Plaintiff-Appellant,

              v.                                              No. 16-cv-498-jdp
                                                              James D. Peterson,      Chief
ROCK ON THE RIVER, INC., et al.,                              Judge.
      Defendants-Appellees.


                                             Order

    While attending the “Rock on the River” music festival just outside Prairie du Chien,
Wisconsin, in 2013, Joshua Milligan was beaten and severely injured by another patron.
This suit by Milligan’s guardian seeks damages from the festival’s sponsors under Wis-
consin law—both the common law and Wis. Stat. §101.11. The litigants agree that re-
covery depends on showing that the sponsors were negligent in providing security for
the patrons. Milligan tried to show negligence principally through the opinion of Rus-
sell Kolins.
No. 18-1204                                                                            Page 2


    Defendants contended that Kolins had not applied his skills and knowledge reliably
to show either deficiencies in the festival’s security or how any deficiencies led to Milli-
gan’s injury. The district court ruled that Kolins’s opinion is inadmissible under Fed. R.
Evid. 702 and that, without his opinion, the record would not permit a reasonable jury
to find for Milligan. The court awarded summary judgment to the defendants. 2017 U.S.
Dist. LEXIS 213195 (W.D. Wis. Dec. 29, 2017).

    Rule 702(d) provides that an expert’s evidence is admissible only if “the expert has
reliably applied the [expert’s] principles and methods to the facts of the case.” The dis-
trict court found Kolins’s report deficient on that ground, because it announces conclu-
sions without giving reasons for them. Appellate review of this ruling is deferential.
Kumho Tire Co. v. Carmichael, 

, 152–53 (1999); General Electric Co. v. Joiner, 

(1997). The district judge did not make a legal error in demanding reasons. “An
expert who supplies nothing but a bottom line supplies nothing of value to the judicial
process.” Mid-State Fertilizer Co. v. Exchange National Bank, 

, 1339 (7th Cir.
1989). And the judge’s application of Rule 702(d) to the facts is well supported.

    Kolins stated that an event needs at least one security person per 250 patrons. This
festival had one per 86 patrons, well above that standard. Kolins asserted that the lay-
out of a venue, and other attributes of a festival, can require additional security but did
not explain what made a ratio of 1 per 86 inadequate at this venue. Instead he criticized
the defendants for not having a security detail on the scene of the attack—outside the
porta potties in a campground, during (or perhaps at the end of) a concert. And it is
true enough that having a numerically adequate security staff does not protect the pa-
trons if the staff is poorly distributed. (Imagine if all 29 persons hired to safeguard this
festival were off by themselves drinking beer when Milligan was attacked.) If the toilets
at a festival were a known place of danger—compared with, say, the mosh pit at the
concert, or compared with the entry areas where weapons could be confiscated—then
the festival would need to make sure that it was guarded. But Kolins did not analyze
the relative risks of the different areas within this 98-acre venue and did not provide ei-
ther data or reasoning suggesting that the toilet area needed more attention and some
other area less at the time of the attack. Indeed, Kolins did not relate that the toilet area
had been the site of injury at this festival in other years, or that toilet areas are danger-
ous at other music festivals.

    Kolins asserted that the security personnel did not do enough to identify and eject
drunken patrons, but the record does not contain evidence that the attacker was drunk
or that a reasonable security staff would have identified him as dangerous. Kolins also
asserted that the festival should have supplied more lighting in the toilet area, but he
did not explain why—he did not, for example, identify data showing the relation be-
No. 18-1204                                                                               Page 3


tween lighting levels and the prevalence of injuries. Nor did he explain why it would
have been sensible to put high-intensity lighting in a campground area designed for
sleeping. All in all, it is difficult to avoid the district court’s conclusion that the ratio of
conclusions to reasons in Kolins’s report was untenably high, making the report inad-
missible. We agree with the judge that a reasonable jury could not rule in Milligan’s fa-
vor without the aid of Kolins’s testimony, which means that the judgment must be

                                                                                      AFFIRMED.