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              OSBORN v. WATERBURY—DISSENT

   KAHN, J., with whom ROBINSON, C. J., and McDON-
ALD, J., join, dissenting. I respectfully disagree with
the majority’s conclusion that the Appellate Court incor-
rectly concluded that the number of supervisors neces-
sary to provide adequate supervision on an elementary
school playground is not within the field of ordinary
knowledge and experience of judges and jurors and,
therefore, expert testimony was required. See Osborn
v. Waterbury, 181 Conn. App. 239, 246, 185 A.3d 675
(2018); see also, e.g., Doe v. Hartford Roman Catholic
Diocesan Corp., 317 Conn. 357, 375, 119 A.3d 462 (2015);
LePage v. Horne, 262 Conn. 116, 125, 809 A.2d 505
(2002). The present case demonstrates that the question
of what constitutes adequate supervision of children
on a school playground is a complex one, not readily
resolved by a fact finder without the assistance of
expert testimony. Given the procedural and factual
background of the present case, I would conclude that
the plaintiffs, Tatayana Osborn (child) and Tacarra
Smith, were required to introduce expert testimony to
establish the applicable standard of care. Therefore, I
respectfully dissent.
   The unfortunate incident that gave rise to this case
has clearly impacted the life of a child. The child, at
the time a fifth grade student at a Waterbury public
elementary school, was attacked by her peers on the
playground at recess, resulting in two lacerations on
her face—one of which resulted in a permanent scar—
and recurring headaches. Keeping children safe while
they are at school is of the utmost importance to cities,
boards of education, and schools, and the provision
of adequate supervision serves the goals of engaging
students and keeping playgrounds safe. Unfortunately,
even with the most stringent supervision, fights, bul-
lying, and accidents occur on playgrounds. See, e.g.,
Despres v. Greenwich Boys & Girls Club Assn., Inc.,
Docket No. CV-XX-XXXXXXX-S, 1999 WL 487565, *5 (Conn.
Super. July 2, 1999) (‘‘[e]ven assuming arguendo that
there was one supervisor, supervising only one child,
standing directly below her and warning her to use the
monkey bars properly by not skipping any bars, it is
still possible that the plaintiff could fall off and injure
her elbow’’). Therefore, when an incident such as this
occurs on a playground during recess, the question of
adequate supervision turns on whether the school made
reasonable efforts to prevent a risk of injury to children
on the playground. See Santopietro v. New Haven, 239
Conn. 207, 228–30, 682 A.2d 106 (1996) (concluding
that plaintiff failed to prove, by expert testimony, that
softball umpires breached their duty of care to prevent
unreasonable risk of injury to spectators).
  In the present case, the principal of the elementary
school at the time of the incident testified at trial that
the defendant Waterbury Board of Education (board)
had a supervision policy requiring a minimum of 1
supervisor for every 125 students on the playground.1
That testimony was the only evidence presented at trial
regarding an appropriate supervisor to student ratio.2
The trial court found, in its memorandum of decision,
that ‘‘1 student intern and 3—or 4—staff members were
not sufficient to exercise proper control over perhaps
as many as 400 students.’’3 As found by the trial court,
there was a maximum of 400 students and a minimum
of 4 supervisors on the playground at the time of the
incident, resulting in a supervisor to student ratio of
1:100.4 The trial court concluded that this ratio of super-
visors to students was insufficient to satisfy the duty
of the defendants, the city of Waterbury and the board,5
to make reasonable efforts to prevent a risk of injury
to the children on the playground. The trial court’s
finding, that there was an inadequate number of supervi-
sors on the playground at the time of the incident, was
the sole basis for its conclusion that the defendants
were liable for negligent supervision. By predicating its
conclusion on a ratio that exceeded the only one testi-
fied to at trial—the board’s policy of 1:125—the trial
court not only held that supervision was inadequate
under the circumstances of this case, but also implicitly
concluded that the board’s policy does not comply with
the applicable standard of care. The issue presented in
this appeal, therefore, is whether expert testimony was
required to enable the trier of fact to determine that
the defendants’ supervision of the playground was negli-
gent, notwithstanding the fact that the supervisor to
student ratio complied with or exceeded the goals set
forth in the board’s policy.6
   The trial court’s determination of whether expert tes-
timony was required to support the plaintiffs’ claim of
negligence against the defendants was a legal deter-
mination subject to plenary review. See, e.g., Doe v.
Hartford Roman Catholic Diocesan Corp., supra, 317
Conn. 373. ‘‘[E]xpert testimony . . . serves to assist
lay people, such as members of the jury and the pre-
siding judge, to understand the applicable standard of
care and to evaluate the defendant’s actions in light of
that standard. . . . Expert testimony is required when
the question involved goes beyond the field of ordi-
nary knowledge and experience of judges or jurors.’’
(Citation omitted; internal quotation marks omitted.);
LePage v. Horne, supra, 262 Conn. 125; see also Doe v.
Hartford Roman Catholic Diocesan Corp., supra, 374;
Doe v. Yale University, 252 Conn. 641, 686–87, 748 A.2d
834 (2000) (‘‘[w]hether expert testimony was required
to support the plaintiff’s claim compels us to consider
whether the determination of the standard of care
requires knowledge that is beyond the experience of
[the] fact finder’’ [internal quotation marks omitted]).
  The question of whether expert testimony is required
does not turn solely on whether the issue presented
is one of ordinary or professional negligence. Expert
testimony is most commonly associated with cases that
are ‘‘akin to allegations of professional negligence or
malpractice,’’ such as legal malpractice or medical mal-
practice. Santopietro v. New Haven, supra, 239 Conn.
226; see, e.g., Downs v. Trias, 306 Conn. 81, 88 and n.5,
49 A.3d 180 (2012). Even in professional malpractice
actions, however, expert testimony is not required
‘‘where there is present such an obvious and gross want
of care and skill that the neglect is clear even to a
layperson.’’ (Internal quotation marks omitted.) Davis
v. Margolis, 215 Conn. 408, 416 n.6, 576 A.2d 489 (1990).
In many cases of ordinary negligence, the issues pre-
sented at trial may be matters of common knowledge
with which the fact finder has familiarity and, therefore,
no expert is needed to testify as to the standard of care
and whether the defendant breached that duty. In other
cases of ordinary negligence, however, issues related
to the standard of care and whether that duty was
breached are beyond the ken of the average fact finder
and expert testimony is required. Therefore, ‘‘[t]he ques-
tion of whether expert testimony is required is not
resolved by characterizing the case as sounding in [pro-
fessional] malpractice or ordinary negligence, but
rather by determining whether the issue, unaided by
expert testimony, is within the realm of a jury’s ordinary
knowledge. Thus, professional negligence claims do not
necessarily require expert testimony, and claims of ordi-
nary negligence may require expert testimony. The
appropriate question is whether the issue can be reliably
decided by a jury without the assistance of expert testi-
mony.’’ Cammarota v. Guerrera, 148 Conn. App. 743,
751, 87 A.3d 1134, cert. denied, 311 Conn. 944, 90 A.3d
975 (2014).
   This court’s reasoning and holding in Santopietro is
directly applicable to the present case. See Santopietro
v. New Haven, supra, 239 Conn. 226–27, 229–32. In
Santopietro, a spectator at a softball game brought a
negligence action against the umpires of the game to
recover for injuries he suffered when he was struck by
a bat thrown by a player. Id., 209. We noted that ‘‘[a]n
umpire obtains, through formal training and experience,
a familiarity with the rules of the sport, a technical
expertise in their application, and an understanding of
the likely consequences of officiating decisions. As a
result, the umpire possesses knowledge of the standard
of care to which an umpire reasonably may be held,
and of what constitutes a violation of that standard,
that is beyond the experience and ken of the ordinary
fact finder.’’ Id., 227. Furthermore, we held that the
‘‘fact finder’s lack of experience [was] exacerbated by
the highly discretionary nature of the umpire’s task’’ to
control the softball game so as to prevent an unreason-
able risk of injury to spectators. Id. Thus, the fact finder
must determine ‘‘not just whether in hindsight the
umpire erred, but also whether the umpire’s error con-
stituted an abuse of his broad discretion.’’ Id. Relying
on these principles, we concluded that the fact finder’s
decision would require specialized knowledge. The
breach of duty, therefore, was required to be proved,
in the absence of exceptional circumstances, by expert
testimony. Id., 229.
   In the present case, the question of whether 4 to 5
supervisors for up to as many as 400 students, as found
by the trial court, was sufficient to satisfy the duty owed
by the defendants is not within the realm of a fact
finder’s ordinary knowledge. Although many fact find-
ers may be familiar with the supervision of children,
and even the supervision of large numbers of children,
that familiarity does not preclude the need for expert
testimony when the fact finder would not be familiar
with the procedures and considerations of education
professionals when determining appropriate supervisor
to student ratios. See Franck v. Minisink Valley School
District, 136 App. Div. 2d 588, 588–89, 523 N.Y.S.2d 573
(1988) (when fifth grade student was kicked in head at
recess by another student doing cartwheels, court held
that, ‘‘[i]n applying the proper standard, familiarity of
the jury with cartwheeling should not preclude expert
testimony where the jury would not be familiar with
accepted professional procedures for supervising cart-
wheeling’’). The need for a board policy setting forth
ratios supports the view that the appropriate supervi-
sion ratio for an elementary school playground based
on the unique circumstances of that setting is not a
simple issue with which every adult would be automati-
cally familiar. Instead, expert guidance is necessary to
establish the standard of care.
   Similar to the umpires’ control of a softball game to
protect spectators from injury, schools and boards of
education develop and apply policies related to the
supervision of students at recess based on their formal
training and experience, familiarity with applicable
rules and statutes, and an understanding of the injuries
that may result if they fail to implement sufficient poli-
cies. In addition, the decision of how many supervisors
is required is complex and highly discretionary in
nature.7 In arranging for appropriate supervision on
playgrounds during recess, consideration should be
given to the size and visibility of the playground area,
the playground equipment, the age and disability status
of the students, and a history of incidents, among other
criteria. See generally Alliance of Schools for Coopera-
tive Insurance Programs, Student Supervision Guide-
lines, p. 3, available at http://ascip.org/wp-content/
uploads/2014/05/Student-Supervision-Guidelines.pdf
(last visited November 22, 2019). There are no set stan-
dards available for appropriate ratios of supervisors to
students, and each play area uniquely determines the
amount of supervision needed. Id.
   I acknowledge that there will be some exceptional
circumstances in which expert testimony is not
required. See Santopietro v. New Haven, supra, 239
Conn. 229; see also David v. Margolis, supra, 215 Conn.
416 n.6 (noting expert testimony is not required, even in
professional negligence cases, ‘‘where there is present
such an obvious and gross want of care and skill that the
neglect is clear even to a layperson’’ [internal quotation
marks omitted]). The present case, however, does not
involve such circumstances. The present situation is
not one in which the trial court found no supervisors
present at recess or found that the supervisors present
were engaged in a nonsupervisory activity and clearly
not paying attention (e.g., on their cell phones), which
would be an obvious want of care clear even to a layper-
son. Instead, the trial court’s findings establish that
there was a supervisor to student ratio of at least 1:100,
and there were no additional findings that would sug-
gest that exceptional circumstances demonstrated a
gross want of care. Because the standard of care to
which a board may reasonably be held in providing
adequate supervision and what constitutes a violation
of that standard are beyond the ken of the ordinary fact
finder, and there are no extraordinary circumstances
present that would demonstrate an obvious and gross
want of care to the ordinary fact finder, I would hold
that expert testimony was required in the present case.
   While this court has not had previous occasion to
apply the principles of Santopietro to the playground
supervision context, our trial courts have done so and
applied similar reasoning. See, e.g., Miller v. Bridgeport,
Docket No. CV-XX-XXXXXXX-S, 2017 WL 1333986 (Conn.
Super. March 20, 2017), aff’d, 188 Conn. App. 901, 201
A.3d 1160 (2019); Despres v. Greenwich Boys & Girls
Club Assn., Inc., supra, 1999 WL 487565, *4–5. In Des-
pres, a student attending an after-school program
claimed that the Greenwich Boys and Girls Club Associ-
ation, Inc., provided negligent supervision when the
student was injured on the playground after falling from
the monkey bars. Despres v. Greenwich Boys & Girls
Club Assn., Inc., supra, *1, 2. At the time, there was ‘‘no
written policy for child supervision and no mandatory
adult-child ratio,’’ but ‘‘the informal policy of the facility
was that one supervisor would be responsible for ten
to fifteen children depending on the activity.’’ Id., *2.
The trial court found that, at the time of the incident,
there were no more than fifteen children on the play-
ground and one supervisor, which was in compliance
with the unwritten policy. Id. The trial court also made
explicit findings that the supervisor was ‘‘positioned in
a place where she could see the entire playground area
and performed the ‘seven second scan’ which she
learned from her experience as a lifeguard . . . and
nothing unusual was happening that afternoon . . . .’’
Id., *4. In that case, the trial court relied on the reasoning
of this court in Santopietro, which held that, ‘‘ ‘[i]f the
determination of the standard of care requires knowl-
edge that is beyond the experience of an ordinary fact
finder, expert testimony will be required.’ ’’ Id., *4 (quot-
ing Santopietro v. New Haven, supra, 239 Conn. 226).
The trial court in Despres, finding that a determination
of the standard of care of the supervisors of an after-
school program and whether that duty was breached
was beyond the experience of an ordinary fact finder,
concluded that expert testimony was required and that,
‘‘[w]ithout such expert testimony, there [was] no evi-
dence that the defendant provided careless or negligent
supervision of the plaintiff.’’ Despres v. Greenwich
Boys & Girls Club Assn., Inc., supra, *5.
   In Miller, a three year old child attended a program
at Skane Center School run by the Bridgeport Board
of Education. See Miller v. Bridgeport, supra, 2017 WL
1333986, *1. Each school day, three or four classes of
students participated in recess at the same time and
all of the teachers and paraprofessionals from each
classroom would supervise the recess. Id., *2. The plain-
tiff was struck by a tricycle being ridden by another
student at recess and suffered injuries; the plaintiff then
brought a negligent supervision claim against the defen-
dant Bridgeport Board of Education. Id. The trial court
found that ‘‘[t]he evidence before the court fail[ed] to
establish that the defendant was negligent as alleged.
There was no evidence from any expert witnesses that
the defendant’s conduct with regard to the amount of
supervision that they provided students during recess
was inadequate or failed to meet appropriate educa-
tional standards for schools such as Skane.’’ Id., *3. In
concluding that the plaintiffs failed to prove that the
defendant was negligent, the trial court specifically
found that ‘‘there was a lack of expert testimony with
regard to the applicable standard of care and whether
that duty was breached’’ as well as ‘‘an absence of
evidence that the conduct of the defendant and any of
its employees violated a school policy or directive . . .
[and] [t]he plaintiff did not provide evidence of any rule,
policy, or directive requiring the defendant to undertake
any specific safety precautions in connection with the
activities conducted during recess.’’ Id.
   Because, in the present case, the sole basis of the
trial court’s conclusion that the defendants’ supervision
of the children was negligent was the supervisor to
student ratio, an expert witness should have been
required and, without one, the plaintiffs failed to meet
their evidentiary burden. I agree with the Appellate
Court that ‘‘the plaintiffs failed to present expert testi-
mony as to the standard of care related to the number
of supervisors needed on an elementary school play-
ground to ensure the safety of the students during
recess’’ and that ‘‘[t]he plaintiffs also failed to present
expert testimony that the number of staff on the play-
ground supervising the children at the time [of the inci-
dent] constituted a breach of the standard of care.’’
Osborn v. Waterbury, supra, 181 Conn. App. 247.
Because these determinations are beyond the knowl-
edge and experience of the ordinary fact finder, the
Appellate Court correctly concluded that the trial court
erred as a matter of law by not requiring expert tes-
timony.8
      For these reasons, I respectfully dissent.
  1
     The written policy, however, was not admitted into evidence, and the
court made no finding in that regard. The following testimony was given
by the principal at trial:
   ‘‘[The Plaintiff’s Counsel]: Okay. Now, as far as you’re concerned, did you
ever give your paraprofessionals and your staff any training having to do
with harassment and bullying?
   ‘‘[The Witness]: We’ve had a lot of different things regarding that.
   ‘‘[The Plaintiff’s Counsel]: Okay. And prior to [April], 2012, for that school
year, what training did you give them?
   ‘‘[The Witness]: We had had reviewed the definition of bullying, talked
about, you know, being proactive, monitoring, you know, areas of the school,
the—where those transition areas are, at recess, at lunch, all the down
times, PE, different areas. We had a guidance counsel[or] who spoke with
the classes as well, participated in our, you know, staff meetings if it occurred
on days that they were in the building.
   ‘‘[The Plaintiff’s Counsel]: And part of that procedure was to have recess
monitors out there, so to speak, is that correct, I believe on the recess
grounds?
   ‘‘[The Witness]: Well, they’re required out there to begin with. It wasn’t
added because of—
   ‘‘[The Plaintiff’s Counsel]: And they’re required why?
   ‘‘[The Witness]: For safety and monitoring of all students.
   ‘‘[The Plaintiff’s Counsel]: Okay. And were you the one [who] made
this requirement?
   ‘‘[The Witness]: No, it was from the [board] and, you know, in the handbook
for policies and procedures.
   ‘‘[The Plaintiff’s Counsel]: All right. And do you know how many people
were required at the recess and who they would be?
   ‘‘[The Witness]: By the [board], the policy was 1—1 staff to 125 students.’’
   2
     I agree with the majority that the record on appeal could be clearer as
to whether the policy was in effect at the time of the incident. I disagree,
however, with the majority’s suggestion that there was not enough evidence
in the record to allow the trial court, as fact finder, to draw the reasonable
inference that the policy testified to by the principal was one that was in
existence and applicable at the time of the incident.
   3
     On appeal to this court, the parties do not dispute the trial court’s findings
and, therefore, I do not review the underlying factual basis of this finding.
I offer, however, the following observations. The testimony at trial described
varying numbers of children on the playground at the time of the incident.
The paraprofessional who arrived first to the incident testified that there
were no more than fifty students on the playground at the time the fight
occurred. The principal testified that there were approximately 400 students
in the entire school from kindergarten through fifth grade, and that those
students ate lunch in 3 waves. The principal further testified that fourth
and fifth grade students ate lunch together, there were 3 classes of each
grade for a total of 6 classes, and there were about 25 students in each
class, totaling 150 students in the lunch wave in question. When the students
had finished eating lunch, they left the cafeteria and went to the playground
for recess. There was no testimony that conflicted with these statements
by the principal and, in fact, the plaintiffs’ lawyer in his closing argument
before the trial court conceded that there were probably between 90 and
150 students on the playground at the time of the incident. Despite this
testimony, the trial court found that the entire school ate lunch and attended
recess at the same time. In addition, ‘‘perhaps as many as 400 students’’ is
an indeterminate number of students that encompasses everything from a
handful of students to 400 students, for which 4 or 5 total supervisors may
have been sufficient.
   4
     If I consider the maximum number of students and the maximum number
of supervisors on the playground at the time of the incident found by the
trial court, then there was a supervisor to student ratio of 1:80.
   5
     See footnote 1 of the majority opinion for other individuals named as
defendants in the plaintiffs’ complaint.
   6
     Although rules and policies do not establish the standard of care, under
these circumstances, an expert should have been required to testify as to
the standard of care and whether the board’s policy failed to meet that
standard of care. See, e.g., Van Steensburg v. Lawrence & Memorial Hospi-
tals, 194 Conn. 500, 506, 481 A.2d 750 (1984) (‘‘[W]e point out that hospital
rules, regulations and policies do not themselves establish the standard of
care. . . . The failure to follow such rules and regulations is, however,
evidence of negligence.’’ [Citations omitted.]).
   7
     Our legislature recognized the important role that supervision plays in
the prevention of bullying and intervention strategies regarding bullying,
and acknowledges that effective strategies may include ‘‘adequate adult
supervision of outdoor areas, hallways, the lunchroom and other specific
areas . . . .’’ General Statutes § 10-222g. The development of policies by
schools and boards that provide for adequate supervision of students to
prevent bullying or to promote general safety is a complicated process. In
recognition of this complexity, the Department of Education has compiled
various resources to provide guidance on the provision of safe playgrounds
and made them available through the Connecticut government website. The
website includes links to federal resources provided by the United States
Departments of Education, Health and Human Services, and Justice as well
as other organizations, such as the Peace Education Foundation and Peaceful
Playgrounds, which can be consulted when developing individual plans
and playgrounds. See Connecticut Department of Education, Bullying and
Harassment, available at https://portal.ct.gov/SDE/School-Climate/Bullying-
and-Harassment/Related-Resources (last visited November 22, 2019).
   8
     The second certified issue was: ‘‘Did the plaintiffs receive adequate notice
of the need for expert testimony to determine the scope of the duty of care
such that a directed judgment was appropriate in this case?’’ Osborn v.
Waterbury, 329 Conn. 901, 184 A.3d 1214 (2018). It is unclear precisely what
the plaintiffs are arguing. The plaintiffs appear to suggest that the defendants’
claim in their closing argument before the trial court, that the plaintiffs
improperly failed to meet their evidentiary burden in the absence of expert
testimony, suggested that the plaintiffs’ claim sounded in professional negli-
gence and not ordinary negligence. The plaintiffs then claim on appeal to
this court that the defendants were required to provide the plaintiffs with
notice that expert testimony was required. I find no merit in the plaintiffs’
argument. The plaintiffs rest their argument on the premise that requiring
an expert witness transforms the present case from one of ordinary negli-
gence to one of professional malpractice, thereby altering the standard of
care. This proposition mischaracterizes the need for expert testimony in
negligence claims. The use of an expert witness to support a claim of
ordinary negligence case does not transform it into a claim of professional
malpractice. As this court has made clear, ‘‘professional negligence claims
do not necessarily require expert testimony, and claims of ordinary negli-
gence may require expert testimony. The appropriate question is whether
the issue can be reliably decided by a jury without the assistance of expert
testimony.’’ Cammarota v. Guerrera, supra, 148 Conn. App. 751. Therefore,
even though the plaintiffs’ claim sounded in ordinary negligence, an expert
could have—and, in the present case, should have—been required. In addi-
tion, the burden is on the plaintiffs to present sufficient evidence at trial to
support their claim of negligent supervision. There is no requirement that
the defendants alert the plaintiffs or the court when that burden is not met
in order to provide the plaintiffs an opportunity to present more evidence.
The plaintiffs were on notice from the time they filed their original complaint
that they were required to meet their evidentiary burden that the defendants
were negligent in their supervision of students on the playground. Without
expert testimony, they failed to do so. For these reasons, I would hold that
the defendants were not required to provide notice to the plaintiffs that
they failed to meet their evidentiary burden without expert testimony.
