Title: People v. Cooper
Citation: N/A
Docket Number: S273134
State: California
Issuer: California Supreme Court
Date: May 25, 2023

IN THE SUPREME COURT OF 
CALIFORNIA 
 
THE PEOPLE, 
Plaintiff and Respondent, 
v. 
ROBERT COOPER, 
Defendant and Appellant. 
 
S273134 
 
Second Appellate District, Division Six 
B304490 
 
Los Angeles County Superior Court 
TA140718 
 
 
May 25, 2023 
 
Justice Groban authored the opinion of the Court, in which 
Chief Justice Guerrero and Justices Corrigan, Liu, Kruger, 
Jenkins, and Evans concurred. 
 
1 
PEOPLE v. COOPER 
S273134 
 
Opinion of the Court by Groban, J. 
 
Assembly Bill No. 333 (2021–2022 Reg. Sess.) (Assembly 
Bill 333), effective January 1, 2022, amended the substantive 
offense of active participation “in a criminal street gang” as well 
as the sentencing enhancement available for a felony committed 
“for the benefit of, at the direction of, or in association with a 
criminal street gang, with the specific intent to promote, 
further, or assist in criminal conduct by gang members.”  (Stats. 
2021, ch. 699, § 3; Pen Code, § 186.22, subds. (a), (b)(1).)1  Among 
other changes, Assembly Bill 333 now requires that, in order to 
demonstrate a pattern of criminal gang activity for the purpose 
of establishing a criminal street gang, the prosecution must 
prove that the two predicate offenses “commonly benefited a 
criminal street gang, and the common benefit from the offenses 
is more than reputational.”  (§ 186.22, subd. (e)(1).)2   
 
1  
 All further unspecified statutory references are to the 
Penal Code. 
2  
In order to establish that a gang is in fact a criminal street 
gang within the meaning of the California Street Terrorism 
Enforcement and Prevention Act (STEP Act), the prosecution 
must prove that gang members “collectively engage in, or have 
engaged in, a pattern of criminal gang activity.”  (§ 186.22, subd. 
(f).)  We refer to the offenses that are used to establish “a pattern 
of criminal gang activity” under the STEP Act as predicate 
offenses.  (§ 186.20 et seq.; see People v. Valencia (2021) 
11 Cal.5th 818, 829.)  
PEOPLE v. COOPER 
Opinion of the Court by Groban, J. 
 
2 
Defendant Robert Cooper was convicted of first degree 
murder (§ 187, subd. (a)) with gang (§ 186.22, subd. (b)(1)(C)) 
and firearm enhancements (§§ 186.22, subd. (b), 12022.53, 
subds. (b)–(e)), and a prior strike conviction (§§ 667, subds. (b)–
(i), 1170.12, subds. (a)–(d)).  We granted review in this case to 
determine whether any of Cooper’s sentencing enhancements 
must be vacated due to this recent statutory change to section 
186.22.3  The parties as well as the Court of Appeal below all 
agree that Cooper’s jury was instructed under the prior law, that 
the new requirements in section 186.22 apply retroactively to 
Cooper’s case on appeal under In re Estrada (1965) 63 Cal.2d 
740, and that the prejudice from the instructional error is 
assessed under Chapman v. California (1967) 386 U.S. 18 
(Chapman).  (See People v. Tran (2022) 13 Cal.5th 1169, 1207 
[the rule of Estrada applies to Assem. Bill 333’s changes to § 
186.22 and any instructional error resulting from the change in 
law is assessed under Chapman].)  Applying the Chapman 
standard, we hold that the failure to instruct that the alleged 
predicate offenses must have “commonly benefited” the gang in 
a “more than reputational” manner (§ 186.22, subd. (e)(1)) was 
not harmless beyond a reasonable doubt.  Here, the record 
contains evidence that could rationally lead to a contrary finding 
regarding whether the gang as a whole (as opposed to the 
predicate offenders themselves) benefited from the offenses in a 
nonreputational 
manner. 
 
We 
reverse 
Cooper’s 
gang 
enhancement, as well as the firearm enhancement that is 
contingent upon the gang enhancement, and remand the case to 
 
3  
Cooper’s first degree murder conviction is not at issue in 
this appeal. 
PEOPLE v. COOPER 
Opinion of the Court by Groban, J. 
 
3 
the Court of Appeal with instructions to remand the case to the 
superior court for any retrial of the same. 
I. Background 
Cooper was a member of the Lueders Park gang.4  Nicos 
Mathis and Monique Peterson were members of a rival gang, 
Mob Piru.  On October 24, 2012, the three were all in Gonzales 
Park in Compton with a large group of people.  Mathis 
challenged Cooper to a fight, but Cooper declined and walked 
away. 
About 20 minutes later, a Buick drove into the park.  
Peterson recognized the two occupants of the Buick as Lueders 
Park gang members and urged Mathis to leave.  Mathis refused 
to leave because he was waiting for a fellow gang member 
nicknamed “Hit Man.”  Eventually Mathis drove away looking 
for Hit Man with Peterson and two other friends.  Mathis pulled 
over on the street where Hit Man had told him to meet.  Peterson 
heard gunshots, and told Mathis to drive away, but they 
remained parked. 
Peterson testified that she turned and saw two cars pull 
up, the Buick and an Infiniti.  Cooper, “Mousey,” and “Honcho” 
were in the Infiniti.  She saw two guns fire toward the vehicle 
she was in.  One of the guns was fired from the front passenger 
side of the Infiniti and the other from the rear passenger side.  
The Buick crashed into Mathis’s car but drove away.  Mathis 
was shot once in the head and four times in the body and later 
died of his wounds in the hospital. 
 
4  
The brief summary of facts is drawn from the Court of 
Appeal’s opinion. 
PEOPLE v. COOPER 
Opinion of the Court by Groban, J. 
 
4 
An information charged Cooper with conspiracy to commit 
murder (§ 182, subd. (a)(1)); the murder of Mathis (§ 187, subd. 
(a)); and three counts of attempted murder (§§ 664, 187, subd. 
(a)).  Each count also alleged firearm allegations (§ 12022.53, 
subds. (b), (c), (d), & (e)(1)), and that the crimes were committed 
for the benefit of, at the direction of, or in association with a 
gang (§ 186.22, subd. (b)(1)(C)).  The information also alleged a 
prior strike conviction (§§ 667, subds. (b)–(i), 1170.12, subds. 
(a)–(d)). 
A jury initially acquitted Cooper of three counts of 
attempted murder (§§ 664, 187, subd. (a)), but hung on a murder 
count (§ 187, subd. (a)) and conspiracy to commit murder count 
(§ 182, subd. (a)(1)).  A retrial was held on the murder count 
only, with the gang (§ 186.22, subd. (b)(1)) and firearm 
enhancements alleged as before (§ 12022.53, subds. (b)–(e)).  
The jury then convicted Cooper of first degree murder (§ 187, 
subd. (a)) and found true the gang (§ 186.22, subd. (b)(1)) and 
firearm enhancements (§ 12022.53, subds. (b)–(e)).  The trial 
court accepted Cooper’s admission that he had suffered a prior 
strike conviction.  (§§ 667, subds. (b)–(i), 1170.12, subds. (a)–(d).)  
The trial court sentenced Cooper to 75 years to life in prison, 
consisting of 25 years to life for the murder, doubled by the 
strike, plus a consecutive 25 years to life for the firearm 
enhancement pursuant to section 12022.53, subdivisions (d) and 
(e)(1).  The trial court stayed the remaining gun and gang 
enhancements. 
At the retrial, the jury was instructed on the gang 
enhancement pursuant to the former section 186.22 with 
CALCRIM No. 1401.  The jury was instructed that to prove the 
gang enhancement, the prosecution must prove the “defendant 
committed or attempted to commit the crime for the benefit of, 
PEOPLE v. COOPER 
Opinion of the Court by Groban, J. 
 
5 
at the direction of, or in association with a criminal street gang; 
and [¶] That the defendant intended to assist, further, or 
promote criminal conduct by gang members.”  The jury was 
instructed that the definition of a “criminal street gang” 
requires a “pattern of gang activity” and “as one or more of its 
primary activities,” the commission of the predicate offenses of 
robbery and the sales of narcotics.  To establish a “pattern of 
gang activity,” the prosecution must prove “at least one of” the 
predicate robbery and the sales of narcotics offenses and that 
the offenses “were committed on separate occasions or were 
personally committed by two or more persons.”  Pursuant to the 
former law, the jury was instructed that the predicate offenses 
“if any, that establish a pattern of criminal gang activity, need 
not be gang-related.”  The jury was not instructed, as Assembly 
Bill 333 now requires, that the predicate offenses, if any, must 
have “commonly benefited [the] criminal street gang, and the 
common benefit from the offenses is more than reputational.”  (§ 
186.22, subd. (e)(1).) 
The records of conviction and gang expert testimony 
establishing the predicate offenses at the retrial show that two 
Lueders Park gang members committed one crime each: Ricky 
Lee Vaughn committed a robbery in violation of section 211 in 
2012 and Donald Wayne Mahan sold narcotics in violation of 
Health and Safety Code section 11351.5 in 2012.5  The gang 
expert testified that both Vaughn and Mahan are Lueders Park 
gang members.  The gang expert had contacted Vaughn 
“numerous times” and Vaughn has “identified himself as a 
 
5  
The Court of Appeal states this narcotics sale occurred in 
2016, but the record of conviction and gang expert testimony 
reflect it occurred in 2012. 
PEOPLE v. COOPER 
Opinion of the Court by Groban, J. 
 
6 
[Lueders] Park Piru gang member.” The gang expert testified 
that Mahan’s son “Doc” is “[p]robably the most senior [Lueders] 
Park Piru gang member on the street right now.”  He also 
testified that the Lueders Park gang claims territory in 
Compton and its primary activities are “theft, burglary, robbery, 
vehicle theft, narcotic sales, narcotic possession, weapons sales, 
weapons possession, assault to murder.”  The gang expert 
explained that “most gang members play that role of a gang 
member and act hard.  But there’s a specific group within each 
specific gang that are really your most active guys.”  He added: 
“They’re out there going on missions, they’re doing shootings, 
they’re doing robberies, they function to do gang banging things.  
And that gets that gang’s name out there.”  The gang expert 
further testified that through the generations, Lueders Park has 
had “different groups that do robberies, shootings, run girls, 
[and] sell narcotics.”  
In response to a hypothetical question, the gang expert 
testified to how the underlying murder benefited the gang, but 
did not testify as to how the alleged predicate offenses benefited 
the gang.  The gang expert explained that a murder like the one 
in this case would benefit the gang by eliminating a rival and by 
maintaining respect, but that money is the “number one” gang 
function. 
During the pendency of Cooper’s appeal, Assembly Bill 
333 amended section 186.22’s definition of a “criminal street 
gang” to require proof of additional elements.  As relevant here, 
in order to prove “a pattern of criminal gang activity” for the 
purpose of establishing a criminal street gang, the prosecution 
must now prove both that the required predicate offenses 
“commonly benefited [the] criminal street gang” and that “the 
common benefit from the offenses is more than reputational.”  
PEOPLE v. COOPER 
Opinion of the Court by Groban, J. 
 
7 
(Stats. 2021, ch. 699, § 3; § 186.22, subd. (e)(1).)  Assembly Bill 
333 clarifies that “Examples of a common benefit that are more 
than reputational may include, but are not limited to, financial 
gain or motivation, retaliation, targeting a perceived or actual 
gang rival, or intimidation or silencing of a potential current or 
previous witness or informant.”  (Stats. 2021, ch. 699, § 3; § 
186.22, subd. (g).)6   
Based upon the evidence presented at the retrial, the 
Court of Appeal found that the absence of a jury instruction on 
the new requirement that the alleged predicate offenses must 
have “commonly benefited” the gang in a “more than 
reputational” manner (§ 186.22, subd. (e)(1)) was harmless 
beyond a reasonable doubt.  The Court of Appeal reasoned that 
the gang expert “testified that the offenses were committed by 
[Lueders] Park gang members and that robbery and sale of 
narcotics are some of the gang’s primary activities.  The 
evidence was uncontradicted.  The benefit to the gang of robbery 
and sale of narcotics is more than reputational.”  (People v. 
Cooper (Jan. 14, 2022, B304490) [nonpub. opn.].)  We granted 
review. 
II. Discussion 
Cooper argues that the Court of Appeal erred in finding 
that the lack of jury instruction on Assembly Bill 333’s new 
elements was harmless.  Here, the jury was never instructed 
 
6  
Assembly Bill 333 also made several other changes to 
section 186.22 that are not at issue in this appeal.  These 
changes included narrowing the definition of “criminal street 
gang” to “an ongoing, organized association or group of three or 
more persons,” whose members “collectively,” rather than just 
individually, “engage in, or have engaged in, a pattern of 
criminal gang activity.”  (§ 186.22, subd. (f), italics added.) 
PEOPLE v. COOPER 
Opinion of the Court by Groban, J. 
 
8 
that, as Assembly Bill 333 now requires, the predicate offenses 
must have “commonly benefited [the] criminal street gang, and 
the common benefit from the offenses is more than 
reputational.”  (§ 186.22, subd. (e)(1).)  We agree with Cooper 
and find that the absence of jury instruction on this new 
requirement was not harmless beyond a reasonable doubt. 
Chapman holds “that before a federal constitutional error 
can be held harmless, the court must be able to declare a belief 
that it was harmless beyond a reasonable doubt.”  (Chapman, 
supra, 386 U.S. at p. 24.)  The jury instruction here implicates 
Cooper’s due process rights by lessening the prosecution’s 
burden to prove elements of the crime.  (See People v. Harris 
(1994) 9 Cal.4th 407, 438 [“jury instructions in a state criminal 
trial omitting the requirement of proof of every element of a 
crime beyond a reasonable doubt are erroneous under the 
Fourteenth Amendment’s due process clause”].)  The due 
process “requirement of proof beyond a reasonable doubt and the 
Sixth Amendment requirement of a jury verdict are 
interrelated.”  (Sullivan v. Louisiana (1993) 508 U.S. 275, 278.)  
Chapman applies to a jury instruction that omits an element of 
an offense.  (Neder v. United States (1999) 527 U.S. 1, 4.)  When 
a jury instruction has omitted an element of an offense, our task 
“is to determine ‘whether the record contains evidence that 
could rationally lead to a contrary finding with respect to the 
omitted element.’ ”  (People v. Mil (2012) 53 Cal.4th 400, 417 
(Mil), quoting Neder, at p. 19.)7   
 
7  
The Attorney General incorrectly characterizes the 
Chapman inquiry before us as asking whether the jury could 
draw a reasonable inference that the alleged predicate offenses 
 
PEOPLE v. COOPER 
Opinion of the Court by Groban, J. 
 
9 
Since Assembly Bill 333’s new elements did not exist at 
the time of Cooper’s trial, the prosecution made no attempt to 
prove that the alleged predicate offenses provided a more than 
reputational common benefit to the gang and Cooper made no 
such concession.  Instead, the records of conviction and gang 
expert testimony establishing the predicate offenses at the 
retrial merely show that two Lueders Park gang members 
committed one crime each: Ricky Vaughn committed a robbery 
in 2012 and Donald Mahan sold narcotics in 2012.  The gang 
expert also testified that Lueders Park’s primary activities are 
“theft, burglary, robbery, vehicle theft, narcotic sales, narcotic 
possession, weapons sales, weapons possession, assault to 
murder.”  The Attorney General suggests, and the Court of 
Appeal appears to have concluded, that crimes that have an 
inherent financial benefit and that are identified as the gang’s 
primary activities qualify as a common benefit to the gang that 
is “more than reputational” under Assembly Bill 333.  (See 
People v. Cooper, supra, B304490 [“The benefit to the gang of 
robbery and sale of narcotics is more than reputational”].)  
However, the record does not disclose the circumstances 
surrounding the predicate offenses and the prosecution never 
introduced any evidence about how the gang commonly 
benefited from them.  While robbery and the sale of narcotics 
typically provide a financial benefit to the offender, the record 
contains evidence that could rationally lead to a contrary finding 
regarding whether the fruits of the offenses were intended to or 
 
commonly benefited the gang.  This, however, is not the proper 
standard.  As noted above, our task “is to determine ‘whether 
the record contains evidence that could rationally lead to a 
contrary finding with respect to the omitted element.’ ”  (Mil, 
supra, 53 Cal.4th at p. 417.)  
PEOPLE v. COOPER 
Opinion of the Court by Groban, J. 
 
10 
did benefit the gang as a whole.  As the Attorney General 
concedes, robbery and narcotics sales “may of course be 
committed by gang members only for personal gain (which, 
relatedly, may benefit the gang only reputationally).”  Indeed, 
“[n]ot every crime committed by gang members is related to a 
gang.”  (People v. Albillar (2010) 51 Cal.4th 47, 60.)  In this way, 
the question of whether an offense is within the gang’s primary 
activities is distinct from the question of whether a particular 
offense has “commonly benefited a criminal street gang.”  
(§ 186.22, subd. (e)(1).)  A jury determination regarding the 
gang’s primary activities merely constitutes a conclusion about 
the types of activities in which a gang typically engages, 
whereas the question about a common benefit asks about how 
the specific predicate offense actually benefited the gang.  (See 
People v. E.H. (2022) 75 Cal.App.5th 467, 473, 478–480 (E.H.) 
[finding that though the predicate offenses included crimes that 
could, in theory, provide a monetary benefit to the gang, the 
evidence did not show that these predicate offenses actually 
benefited the gang].)  Furthermore, the jury here was 
specifically instructed that the predicate offenses “that establish 
a pattern of criminal gang activity[] need not be gang-related,”  
in accordance with the former law as set forth in People v. 
Gardeley (1996) 14 Cal.4th 605, 621–622, disapproved of on 
other grounds by People v. Sanchez (2016) 63 Cal.4th 665, 686, 
fn. 13.  This instruction directly contradicts Assembly Bill 333’s 
new requirement that the predicate offenses “commonly 
benefited [the] criminal street gang, and the common benefit 
from the offenses is more than reputational.”  (§ 186.22, subd. 
(e)(1).)  Based upon the record, a jury could have reasonably 
concluded that the predicate offenses at issue were committed 
for personal gain alone. 
PEOPLE v. COOPER 
Opinion of the Court by Groban, J. 
 
11 
Moreover, the Attorney General’s interpretation would 
render superfluous much of the new amendment that requires 
both that predicate offenses “commonly benefited” the gang and 
that the common benefit is “more than reputational.”  (§ 186.22, 
subd. (e)(1).)  Section 186.22, subdivision (e)(1) lists numerous 
predicate offenses that typically involve a financial benefit to the 
offender.8  Prior to the amendments, section 186.22, 
subdivisions (e)(1) and (f), which define “pattern of criminal 
gang activity” and “a criminal street gang,” have long required 
that the gang must have “as one of its primary activities the 
commission of one or more of” the enumerated predicate 
offenses.  (§ 186.22, subd. (f).)  The Legislature then decided to 
amend section 186.22 to require a heightened showing both that 
the predicate offenses “commonly benefited a criminal street 
gang” and that the common benefit is “more than reputational.”  
(§ 186.22, subd. (e)(1).)  If all that were required to prove a 
predicate offense is that the prosecution show that the gang 
member committed as one of the gang’s primary activities any 
one of the enumerated predicate offenses that typically involve 
a financial benefit, then the additional requirement that the 
predicate offenses also “commonly benefited a criminal street 
gang” in a “more than reputational” manner would be mere 
surplusage.  Finally, such an interpretation is inconsistent with 
the legislative history indicating the Legislature was concerned 
 
8  
Specifically, the list of predicate offenses in section 186.22, 
subdivision (e)(1) includes: robbery (§ 211 et seq.), sale or 
possession for sale of a controlled substances (Health & Saf. 
Code, § 11007), grand theft (§ 487), grand theft of a firearm or 
vehicle (§ 487, subd. (d)), burglary (§ 459), money laundering 
(§ 186.10), felony extortion (§§ 518, 520), carjacking (§ 215), sale 
of a firearm (§ 27500 et seq.), and vehicle theft (Veh. Code, 
§ 10851). 
PEOPLE v. COOPER 
Opinion of the Court by Groban, J. 
 
12 
with “lax” interpretations of the prior law that allowed for overly 
expansive application of gang enhancements (Stats. 2021, ch. 
699, § 2) and therefore sought to amend the law by “making the 
standards for applying a gang enhancement more rigorous.”  
(Sen. Com. on Public Safety, Analysis of Assem. Bill 333, as 
amended May 28, 2021, p. 6.)9 
The Attorney General tries to save his argument by 
claiming that because Mahan was a “ ‘senior’ ” member of the 
gang and Vaughn was “a well-known” member, a reasonable 
inference is that Mahan and Vaughn were among the “most 
active” gang members committing the gang’s primary activities, 
making it in turn reasonable to infer that they committed the 
predicate offenses for the common benefit of the gang.  However, 
even assuming arguendo that senior or well-known gang 
membership could possibly be evidence that predicate offenses 
commonly benefited the gang, the record does not support the 
Attorney General’s characterization of Mahan and Vaughn as 
senior or well-known members of the gang.  Rather, the gang 
expert testified, when asked if he was familiar with Mahan, that 
“I know Doc, his son.  Doc’s a [Lueders] Park Piru gang member.  
 
9  
At oral argument, defense counsel acknowledged that one 
interpretation of Assembly Bill 333 is that, though the evidence 
presented here does not suffice, it is permissible, as a general 
matter, to use circumstantial evidence to prove a common 
benefit that is more than reputational.  It is also worth noting 
that a financial gain is not the only way that the prosecution can 
prove a more than reputational common benefit to the gang.  
Assembly Bill 333 provides several other examples of a more 
than reputational common benefit, including, but not limited to, 
“retaliation, targeting a perceived or actual gang rival, or 
intimidation or silencing of a potential current or previous 
witness or informant.”  (§ 186.22, subd. (g).) 
PEOPLE v. COOPER 
Opinion of the Court by Groban, J. 
 
13 
Probably the most senior [Lueders] Park Piru gang member on 
the street right now.  Been a long time in prison.  I think he’s 
been out maybe three or four years now.  But just saw him a 
couple weeks ago.  Probably there today.  He sets up on 
Saunders and Bradfield and goes to sell his narcotics.”  The most 
plausible read of this testimony is that the gang expert testified 
that Mahan’s son (and not Mahan himself) was “the most senior” 
Lueders Park gang member.  At a minimum, this testimony does 
not allow us to conclude beyond a reasonable doubt that the 
gang expert was referring to Mahan himself.  Moreover, to the 
extent the Attorney General is suggesting that we can 
determine beyond a reasonable doubt that Mahan was a senior 
gang member simply because a family member was a senior 
gang member, we reject that argument out of hand.  As for Ricky 
Vaughn, though the Attorney General contends that the gang 
expert characterized him as a “well-known” gang member, the 
gang expert actually testified that “I’ve contacted Ricky 
numerous times.  I’ve spoken to Ricky.  He identified himself as 
a [Lueders] Park Piru gang member.  I’ve taken photographs of 
him throwing up the [Lueders] Park Piru Hand sign.  [¶]  I’ve 
recently assisted on another case where Ricky Lee Vaughn has 
identified himself as a [Lueders] Park Piru gang member again.”  
Again, even assuming arguendo that senior or well-known gang 
membership could possibly be evidence that predicate offenses 
commonly benefited the gang, this testimony does not support 
the Attorney General’s characterization.  The gang expert 
testified not that Vaughn was a well-known or senior gang 
member, but simply that Vaughn was known to the gang expert 
through several prior contacts with him. 
In sum, the grand total of evidence relied on by the Attorney 
General for proving that the alleged predicate offenses provided 
PEOPLE v. COOPER 
Opinion of the Court by Groban, J. 
 
14 
a common benefit that is more than reputational to the gang is 
that there was a robbery and a sale of narcotics by gang 
members and that a primary activity of the gang is to commit 
robberies and the sale of narcotics.  Under these circumstances, 
we cannot conclude “beyond a reasonable doubt that the error 
complained of did not contribute to the verdict obtained.”  
(Chapman, supra, 386 U.S. at p. 24.)10   
III. Disposition 
  
For the above reasons, we reverse the Court of Appeal’s 
affirmance of Cooper’s gang enhancement.11  Since the firearm 
 
10  
As Cooper argues, the Court of Appeal’s holding is an 
anomaly among opinions considering Assembly Bill 333 and 
which have reversed gang enhancements.  (E.g., E.H., supra, 
75 Cal.App.5th at pp. 476–480; People v. Lopez (2021) 
73 Cal.App.5th 327, 343–346 (Lopez); People v. Sek (2022) 
74 Cal.App.5th 657, 664–670; People v. Rodriguez (2022) 
75 Cal.App.5th 816, 822–823; People v. Vasquez (2022) 
74 Cal.App.5th 1021, 1032–1033.)  In each case, the predicate 
offenses and the evidence supporting them are different and, as 
the Attorney General maintains, these decisions have 
distinguishing features.  Nevertheless, though we do not here 
decide the unique facts of those cases, Cooper is correct that in 
each case the Court of Appeal reversed a gang enhancement 
after the enactment of Assembly Bill 333 for a trial that occurred 
without Assembly Bill 333’s guidance.  Indeed, the decision 
below is the only Court of Appeal opinion cited in the parties’ 
briefing affirming a gang enhancement after the enactment of 
Assembly Bill 333 for a trial that occurred before Assembly Bill 
333 was enacted. 
11  
As noted above, Assembly Bill 333 also requires that gang 
members “collectively” engage in a pattern of criminal gang 
activity under section 186.22, subdivision (f).  Cooper requests 
that if we do not reverse the gang enhancement based upon the 
new requirement that the predicate offenses commonly benefit 
 
PEOPLE v. COOPER 
Opinion of the Court by Groban, J. 
 
15 
enhancement alleged under section 12022.53, subdivision (e)(1), 
is contingent on a true finding on the gang enhancement under 
section 186.22, we reverse the Court of Appeal’s affirmance of 
that firearm enhancement as well, and remand the case to the 
Court of Appeal with instructions to remand the case to the 
superior court for any retrial of the same.  (See Lopez, supra, 
73 Cal.App.5th at pp. 346–348; E.H., supra, 75 Cal.App.5th at 
p. 480 [“The proper remedy for this type of failure of proof — 
where newly required elements were ‘never tried’ to the jury — 
is to remand and give the People an opportunity to retry the 
affected charges”].) 
 
 
 
 
 
 
GROBAN, J. 
 
We Concur: 
GUERRERO, C. J. 
CORRIGAN, J. 
LIU, J. 
KRUGER, J. 
JENKINS, J. 
EVANS, J. 
 
the gang in a more than reputational way, that we instead 
remand the case to the Court of Appeal so that the failure to 
instruct on the element of collective action by the gang can be 
briefed there.  Cooper has also filed a motion for eventual 
remand or, alternatively, to expand the issues on review based 
upon similar reasons.  Since we are reversing Cooper’s gang 
enhancement on the issue that we granted review upon, 
Cooper’s requests that we remand or expand the issues based 
upon another theory is rendered moot. 
 
 
See next page for addresses and telephone numbers for counsel who 
argued in Supreme Court. 
 
Name of Opinion  People v. Cooper 
__________________________________________________________  
 
Procedural Posture (see XX below) 
Original Appeal  
Original Proceeding 
Review Granted (published) 
Review Granted (unpublished) XX NP opn. filed 1/14/22 – 2d Dist., 
Div. 6 
Rehearing Granted 
__________________________________________________________  
 
Opinion No. S273134 
Date Filed:  May 25, 2023 
__________________________________________________________  
 
Court:  Superior  
County:  Los Angeles 
Judge:  Allen Joseph Webster, Jr. 
__________________________________________________________   
 
Counsel: 
 
Elizabeth K. Horowitz, under appointment by the Supreme Court, for 
Defendant and Appellant. 
 
Rob Bonta, Attorney General, Lance E. Winters, Chief Assistant 
Attorney General, Susan Sullivan Pithey, Assistant Attorney General, 
Michael C. Keller, Idan Ivri and Charles S. Lee, Deputy Attorneys 
General, for Plaintiff and Respondent. 
 
 
 
Counsel who argued in Supreme Court (not intended for 
publication with opinion): 
 
Elizabeth K. Horowitz 
Law Office of Elizabeth K. Horowitz, Inc. 
5272 South Lewis Avenue, Suite 256 
Tulsa, OK 74105 
(424) 543-4710 
 
Charles S. Lee 
Deputy Attorney General 
300 South Spring Street, Suite 1702 
Los Angeles, CA 90013 
(213) 269-6068