Filed 5/6/15

CERTIFIED FOR PUBLICATION

IN THE COURT OF APPEAL OF THE STATE OF CALIFORNIA

SECOND APPELLATE DISTRICT

DIVISION THREE

AMERICAN CIVIL LIBERTIES UNION 

FOUNDATION OF SOUTHERN 

CALIFORNIA et al.,

Petitioners,

v.

THE SUPERIOR COURT OF

LOS ANGELES COUNTY,

Respondent;

COUNTY OF LOS ANGELES et al., 

Real Parties in Interest.

B259392

(Los Angeles County

Super. Ct. No. BS143004)

PETITION for Writ of Mandate from an order of the Superior Court of Los 

Angeles County, James C. Chalfant, Judge. Petition denied.

Peter Bibring for Petitioner American Civil Liberties Union Foundation of 

Southern California.

Jennifer Lynch for Petitioner Electronic Frontier Foundation.

No Appearance for Respondent.

Michael N. Feuer, City Attorney, Carlos De La Guerra, Managing Assistant City 

Attorney, Debra L. Gonzales, Assistant City Attorney, and Heather L. Aubry, Deputy 

City Attorney, for Real Parties in Interest City of Los Angeles and the Los Angeles 

Police Department.
2

Collins Collins Muir + Stewart, Eric Brown, Tomas A. Guterres and James C. 

Jardin for Real Parties in Interest County of Los Angeles and the Los Angeles Sheriff’s 

Department.

_____________________

INTRODUCTION

In this writ proceeding we must determine whether the California Public Records 

Act (CPRA) exemption for law enforcement records of investigations (Gov. Code, 

§ 6254, subd. (f))1applies to records generated by a system of high-speed cameras that 

automatically scan and catalogue license plate images to aid law enforcement in locating

vehicles associated with a suspected crime. We conclude the exemption applies.

For more than a decade, the Los Angeles Police Department (LAPD) and Los 

Angeles Sheriff’s Department (LASD), agencies of Real Parties in Interest the City and 

County of Los Angeles (collectively, Real Parties), have used Automatic License Plate 

Reader (ALPR) technology to automate a process that officers ordinarily perform 

manually—checking license plates to determine whether a vehicle is stolen or otherwise 

wanted in connection with a crime. Real Parties’ ALPR systems consist of specialized 

cameras mounted to patrol cars or stationary structures that scan license plates in their 

immediate vicinity and record the license plate number together with the time and 

location of the scan. At virtually the same time, the ALPR system checks every license 

plate number it scans against a list of known license plates associated with suspected 

crimes—a so-called “hot list.” If the system registers a hit, patrol officers are 

immediately notified that a hot list vehicle is in their vicinity. Regardless of whether 

there is a hit, the system records the plate scan data, which Real Parties retain for up to 

five years for use in future investigations.

 

1

Subsequent statutory references are to the Government Code, unless otherwise 

designated.
3

Petitioners American Civil Liberties Union Foundation of Southern California and 

Electronic Frontier Foundation sent Real Parties a CPRA request for their policies and 

guidelines concerning use of ALPR technology, as well as all ALPR plate scan data Real 

Parties collected during a single week in August 2012. Real Parties agreed to produce the 

policies and guidelines, but refused to disclose the week’s worth of ALPR data, citing the 

law enforcement investigative records exemption and privacy concerns. Petitioners filed 

a petition for writ of mandate seeking to compel production of the ALPR data under the 

CPRA. The trial court denied the petition, concluding the records are exempt as records 

of law enforcement investigations under section 6254, subdivision (f). Guided by 

Supreme Court precedent extending the exemption to “records of investigations 

conducted for the purpose of uncovering information surrounding the commission of the 

violation [of law] and its agency” (Haynie v. Superior Court (2001) 26 Cal.4th 1061, 

1071 (Haynie)), we likewise conclude the exemption applies to records generated by the 

ALPR system in the course of scanning license plates to locate automobiles associated 

with a suspected crime under investigation. Accordingly, we deny the writ petition.

FACTS AND PROCEDURAL BACKGROUND

The relevant facts are not in dispute. Real Parties each maintain an ALPR system 

that consists of several high-speed cameras mounted on fixed structures and patrol cars 

that automatically capture an image of every passing vehicle’s license plate in their

immediate vicinity. The system uses “character recognition software” to read the license 

plate’s number from the image and “almost instantly” checks the number against a list of 

“known license plates” associated with suspected crimes—or a “hot list”—to determine 

whether a vehicle may be stolen or otherwise associated with a crime, AMBER alert or 

outstanding warrant. If a mobile ALPR unit detects a license plate on the hot list, officers 

are notified of the “hit” by an audible alert and notation on their patrol car’s computer 

screen. ALPR fixed positions similarly notify a central dispatch unit when a hit is 

detected.
4

In addition to extracting the license plate number, the ALPR system records the 

date and location where it captured the plate’s image. The system transmits this “plate 

scan data” to an ALPR server within Real Parties’ confidential computer networks. 

LAPD estimates it records plate scan data for approximately 1.2 million cars per week; 

LASD estimates that figure to be between 1.7 and 1.8 million plate scans for its ALPR 

system. LAPD retains plate scan data for five years under its current policy. LASD 

retains the data for two years, although it would prefer to retain the data indefinitely.

In addition to receiving immediate notification from the ALPR system when it 

locates a license plate on the hot list, Real Parties can also query stored plate scan data to 

assist in subsequent law enforcement investigations. For instance, LAPD investigators 

have used stored ALPR data to identify a vehicle that was present at an armed robbery 

and, in another instance, a vehicle directly linked to a homicide. Real Parties maintain 

policies restricting access to plate scan data for law enforcement purposes only.

On August 30 and September 4, 2012, Petitioners sent substantially identical 

CPRA requests to LAPD and LASD seeking records related to those agencies’ use of 

ALPR technology, including “all ALPR data collected or generated” during a one-week 

period in August 2012, consisting of, “at a minimum, the license plate number, date, 

time, and location information for each license plate recorded.” The CPRA request also 

sought “any policies, guidelines, training manuals and/or instructions on the use of ALPR 

technology and the use and retention of ALPR data, including records on where the data 

is stored, how long it is stored, who has access to the data, and how they access the data.”

Real Parties each agreed to produce records responsive to Petitioners’ requests for 

policies, guidelines and training manuals concerning the use, access, and retention of 

ALPR plate scan data. Real Parties refused to produce the requested week’s worth of 

plate scan data, however, citing, among other things, the exemption for records of law 

enforcement investigations.

On May 6, 2013, Petitioners filed a verified petition for writ of mandate to compel 

production of the ALPR plate scan data under the CPRA.
5

Real Parties each opposed the petition, again citing the exemption for records of 

law enforcement investigations under section 6254, subdivision (f), as well as the 

“catchall” exemption under section 6255.2 With their opposition briefs, Real Parties filed 

supporting declarations by their subject matter experts detailing the technical aspects of 

their respective ALPR systems and the ways each law enforcement agency uses the 

technology in practice.

On August 21, 2014, the court held a trial on Petitioners’ writ petition. On August 

27, 2014, the court entered an order affirming Real Parties’ decision to withhold the 

ALPR plate scan data, concluding the data was subject to the records of investigations 

exemption under section 6254, subdivision (f) and the catchall exemption under section 

6255.

DISCUSSION

1. Standard of Review

A trial court order under the CPRA, either directing disclosure by a public official 

or affirming the public official’s decision to refuse disclosure, is immediately reviewable 

by petition to the appellate court for issuance of an extraordinary writ. (§ 6259, subd. 

(c).) “The standard for review of the order is ‘an independent review of the trial court’s 

ruling; factual findings made by the trial court will be upheld if based on substantial 

evidence.’ ” (City of San Jose v. Superior Court (1999) 74 Cal.App.4th 1008, 1016.) 

The interpretation of the CPRA, and application of the statute to undisputed facts is a 

question of law subject to de novo review. (Lorig v. Medical Board (2000) 

78 Cal.App.4th 462, 467.)

 

2 Under section 6255, a public agency may justify withholding records otherwise 

subject to CPRA disclosure requirements by demonstrating that “on the facts of the 

particular case the public interest served by not disclosing the record clearly outweighs 

the public interest served by disclosure of the record.”
6

2. The Records of Investigations Exemption Under Government Code Section 

6254, Subdivision (f)

The CPRA declares that “access to information concerning the conduct of the 

people’s business is a fundamental and necessary right of every person in this state.” 

(§ 6250.) The statute’s explicit purpose is to increase freedom of information by giving 

the public access to information in the public agencies’ possession. (CBS, Inc. v. Block 

(1986) 42 Cal.3d 646, 651.) “Maximum disclosure of the conduct of governmental 

operations was to be promoted by the [CPRA].” (Id. at pp. 651-652.) To that end, the 

CPRA provides that “every person has a right to inspect any public record, except as 

hereafter provided.” (§ 6253, subd. (a).) Hence, “all public records are subject to 

disclosure unless the Legislature has expressly provided to the contrary.” (Williams v. 

Superior Court (1993) 5 Cal.4th 337, 346 (Williams); Haynie, supra, 26 Cal.4th at 

p. 1068.) Consistent with the CPRA’s purpose, “[s]tatutory exemptions from compelled 

disclosure are narrowly construed.” (California State University, Fresno Assn., Inc. v. 

Superior Court (2001) 90 Cal.App.4th 810, 831.)

Real Parties contend, and the trial court found, that the plate scan records 

generated by the ALPR system constitute records of investigations which are exempt 

from disclosure under section 6254, subdivision (f). In pertinent part, subdivision (f) 

authorizes a public agency to withhold “[r]ecords of . . . investigations conducted by . . . 

any state or local police agency, or any investigatory or security files compiled by any 

other state or local police agency . . . .” While broadly shielding the records themselves 

from disclosure, the CPRA requires law enforcement agencies to disclose certain 

information derived from the records, as provided in subdivisions (f)(1) and (f)(2).3 

 

3 Notwithstanding the general directive to narrowly construe such exemptions, our 

Supreme Court has explained that section 6254, subdivision (f) “articulates a broad 

exemption from disclosure for law enforcement investigatory records,” which is limited 

only by requirements in subdivisions (f)(1) and (f)(2) to “provide certain information 

derived from the records about the incidents under investigation.” (Williams, supra, 

5 Cal.4th at p. 349, italics added.) That is, “[i]nstead of adopting criteria that would 

require the exemption’s applicability to be determined on a case-by-case basis,” the 
7

(Williams, supra, 5 Cal.4th at p. 353; Haynie, supra, 26 Cal.4th at p. 1068.) The parties 

agree that the derivative categories of information to be disclosed under these

subsections—information about arrests and arrestees (§ 6254, subd. (f)(1)) and 

complaints and requests for assistance (§ 6254, subd. (f)(2))—are not at issue in this case.

What is at issue is the meaning of the term “investigations” in section 6254, 

subdivision (f), and whether the functions performed by the ALPR system can properly 

be characterized as investigations under the statute. Though the CPRA does not define 

the term, and no case has considered whether records generated by an automated process,

like that performed by the ALPR system, qualify for exemption under subdivision (f), our 

Supreme Court has articulated some general principles to guide our analysis. 

First, the exemption for records of investigation encompasses routine 

investigations undertaken to determine if a violation of law has, or may have, occurred. 

In rejecting an interpretation that would exclude such records from the exemption’s 

purview, the Supreme Court in Haynie explained, “The Court of Appeal, in ordering 

disclosure, reasoned that the citizen report . . . did not ‘necessarily’ describe a crime and 

that the [law enforcement action] was a ‘routine police inquiry’ based on mere suspicion 

of criminal conduct. These factors are of no significance under the statute. In exempting 

‘[r]ecords of complaints to, or investigations conducted by’ law enforcement agencies, 

section 6254(f) does not distinguish between investigations to determine if a crime has 

been or is about to be committed and those that are undertaken once criminal conduct is 

apparent.”4 (Haynie, supra, 26 Cal.4th at p. 1070, fn. 6, italics added.)

 

Legislature “limited the CPRA’s exemption for law enforcement investigatory files . . . 

[by] adopt[ing] a series of amendments that required the disclosure of information 

derived from the records while, in most cases, preserving the exemption for the records 

themselves.” (Id. at p. 353.)

4

This distinguishes the records of investigations from “investigatory . . . files

compiled by any . . . local agency for correctional, law enforcement, or licensing 

purposes. . . .” (§ 6254, subd. (f), italics added.) As the Supreme Court explained in 

Williams, it is “well established that ‘information in public files [becomes] exempt as 

“investigatory” material only when the prospect of enforcement proceedings [becomes] 

concrete and definite.’ ” (Williams, supra, 5 Cal.4th at p. 356.) “Such a qualification is 
8

Second, while routine investigations are within the exemption’s ambit, not 

everything that law enforcement does is shielded from disclosure. As the court explained 

in Haynie, “[o]ften, officers make inquiries of citizens for purposes related to crime 

prevention and public safety that are unrelated to either civil or criminal investigations. 

The records of investigation exempted under section 6254(f) encompass only those 

investigations undertaken for the purpose of determining whether a violation of law may 

occur or has occurred. If a violation or potential violation is detected, the exemption also 

extends to records of investigations conducted for the purpose of uncovering information 

surrounding the commission of the violation and its agency.” (Haynie, supra, 26 Cal.4th 

at p. 1071, italics added.)

Third, the exemption shielding records of investigations from disclosure does not 

lapse when the investigation that prompted the records’ creation ends. As the high court 

stated in Williams with respect to the exemption for investigatory files, “It is noteworthy 

that nothing [in the statute’s language] purports to place a time limit on the exemption for 

investigatory files. Indeed, a file ‘compiled by . . . [a] police agency’ or a file ‘compiled 

by any other state or local agency for . . . law enforcement . . . purposes’ continues to 

meet that definition after the investigation has concluded. If the Legislature had wished 

to limit the exemption to files that were ‘related to pending investigations,’ words to 

achieve that result were available. It is not the province of courts ‘to insert what has been 

omitted.’ ” (Williams, supra, 5 Cal.4th at p. 357.) The same is true for records of 

investigations—they continue to be “[r]ecords of . . . investigations conducted by . . . any 

 

necessary to prevent an agency from attempting to ‘shield a record from public 

disclosure, regardless of its nature, simply by placing it in a file labelled 

“investigatory.” ’ ” (Haynie, supra, 26 Cal.4th at p. 1069, quoting Williams, at p. 355.) 

However, the “ ‘concrete and definite’ qualification to the exemption in section 6254(f) 

‘relates only to information which is not itself exempt from compelled disclosure, but 

claims exemption only as part of an investigatory file. Information independently 

exempt, such as “intelligence information” [or records of investigations at issue in 

Haynie], is not subject to the requirement that it relate to a concrete and definite prospect 

of enforcement proceedings.’ ” (Haynie, at p. 1069, quoting American Civil Liberties 

Union Foundation v. Deukmejian (1982) 32 Cal.3d 440, 449, fn. 10.)
9

state or local police agency” even after the investigation that prompted their creation 

ends. (§ 6254, subd. (f).)

Finally, as alluded to in the foregoing quotation from Williams, the Supreme Court 

has cautioned against courts placing nonstatutory limitations on the scope of section 

6254, subdivision (f). As the court elaborated in Williams, referring to the required 

disclosures under section 6254, subdivisions (f)(1) and (f)(2), “These provisions for 

mandatory disclosure from law enforcement investigatory files represent the 

Legislature’s judgment, set out in exceptionally careful detail, about what items of 

information should be disclosed and to whom. Unless that judgment runs afoul of the 

Constitution it is not our province to declare that the statutorily required disclosures are 

inadequate or that the statutory exemption from disclosure is too broad. . . . Requests for 

broader disclosure must be directed to the Legislature.” (Williams, supra, 5 Cal.4th at 

p. 361.)

With these principles in mind, we turn to whether the plate scan data generated by 

the ALPR system constitute records of investigation under section 6254, subdivision (f).

3. Plate Scan Data Generated by the ALPR System Are Records of 

Investigations Exempt from Disclosure Under Government Code Section 

6254, Subdivision (f)

Drawing on the guidance from Haynie and Williams, Real Parties contend the 

plate scans performed by the ALPR system are “investigations” within the meaning of 

section 6254, subdivision (f) because they are “conducted for the purpose of uncovering 

information surrounding the commission of the violation [of law] and its agency.” 

(Haynie, supra, 26 Cal.4th at p. 1071.) Citing the declaration by LAPD’s subject matter 

expert, Real Parties stress that the ALPR system uses “character recognition software” to 

read license plate numbers and “almost instantly” checks those numbers against a list of 

“known license plate[s]” associated with suspected crimes to “determine whether a 

vehicle may be stolen or otherwise associated with a crime.” The LASD’s declarant 

described the ALPR system’s function in similar terms, explaining that by utilizing the 

system to “automatically” check license plate scans against a “hot list” of plates 
10

associated with suspected crimes, “[t]he [LASD] uses ALPR technology to investigate 

specific crimes that involve motor vehicles, including but not limited to stolen motor 

vehicles, Amber alerts that identify a specific motor vehicle, warrants that relate to the 

owner of a specific motor vehicle, and license plates of interest that relate to a specific 

investigation being conducted by [LASD] investigatory personnel.” Thus, Real Parties 

contend the license plate scan and almost instantaneous check against the hot list 

constitutes an investigation under section 6254, subdivision (f), because the ALPR 

system is attempting to detect and uncover criminal activity. (Haynie, at p. 1071.)

Expanding on the foregoing analysis, Real Parties argue the records generated by 

the ALPR system in performing the scans and hot list checks are records of investigations

and, therefore, exempt from disclosure under section 6254, subdivision (f). As counsel 

for the LASD put it at the trial below, plate scan data generated by the ALPR system is 

necessarily a record of an investigation because “[t]hese records would not exist were the 

County or the City not investigating specific crimes in an attempt to locate persons who 

are suspected of having committed crimes.” We agree. In the Haynie court’s words, 

these records exist only because Real Parties are trying to “uncover[ ] information 

surrounding the commission of [a] violation [of law] and its agency.” (Haynie, supra, 

26 Cal.4th at p. 1071.) As evidenced by the LAPD and LASD declarations, Real Parties 

have deployed the ALPR system to assist in law enforcement investigations involving an 

identified automobile’s license plate number. It follows that the records the ALPR

system generates in the course of attempting to detect and locate these automobiles are 

records of those investigations. The exemption under section 6254, subdivision (f) 

broadly shields these records from disclosure, subject to requirements pertaining to 

derivative information (see § 6254, subds. (f)(1) & (f)(2)) not at issue here. (See 

Williams, supra, 5 Cal.4th at pp. 353, 361; Haynie, at p. 1068.)

Petitioners argue the ALPR plate scans are not investigations within the 

exemption’s purview. Unlike the cases that have applied the exemption, which all 

“involve[d] requests for documents related to targeted investigations of specific criminal 

acts” (italics added), Petitioners argue the plate scans conducted by ALPR systems “are 
11

not precipitated by any specific criminal investigation.” Rather, Petitioners assert, ALPR 

systems “photograph every license plate that comes into view . . . regardless of whether 

the car or its driver is linked to criminal activity.” They contend, ALPR systems “do not 

conduct investigations; they collect data.” We disagree.

Contrary to Petitioners’ premise, the plate scans performed by the ALPR system 

are precipitated by specific criminal investigations—namely, the investigations that 

produced the “hot list” of license plate numbers associated with suspected crimes. As 

Real Parties’ experts both testified, the ALPR system’s principal purpose is to check 

license plates against the hot list to determine whether a vehicle is connected to a crime 

under investigation. In this way, the ALPR system replicates, albeit on a vastly larger 

scale, a type of investigation that officers routinely perform manually by visually reading

a license plate and entering the plate number into a computer to determine whether a 

subject vehicle might be stolen or otherwise associated with a crime.5The fact that the 

ALPR system automates this process does not make it any less an investigation to locate

automobiles associated with specific suspected crimes.

Nor does the fact that the ALPR system scans every license plate within view,

“regardless of whether the car or its driver is linked to criminal activity,” mean the 

system is not performing an investigation. As explained in Haynie, “[i]n exempting 

‘[r]ecords of . . . investigations conducted by’ law enforcement agencies, section 6254(f) 

does not distinguish between investigations to determine if a crime has been or is about 

to be committed and those that are undertaken once criminal conduct is apparent.” 

 

5

Petitioners suggest the “collection of plate data”—i.e., the photographing and 

scanning of a license plate—can be separated from “its later investigative uses”—i.e., the 

near instantaneous check against the hot list. This argument ignores that the plate scan is 

an integral part of the ALPR system’s process for locating automobiles on the hot list. 

Just as an officer cannot investigate whether an automobile has been associated with a 

suspected crime without visually observing and reading its license plate number, so too 

the ALPR system cannot determine whether a license plate number is on the hot list 

without scanning the plate. The collection of plate data and hot list check are part and 

parcel of the same investigative process—without the plate scan there can be no 

investigation.
12

(Haynie, supra, 26 Cal.4th at p. 1070, fn. 6, italics added.) Contrary to Petitioners’ 

implicit contention, our Supreme Court has repeatedly rejected the notion that a “concrete 

and definite” prospect of enforcement must be shown to exempt records of investigations 

from disclosure. (Id. at pp. 1069-1071; see also Williams, supra, 5 Cal.4th at pp. 354-

356.) The ALPR system necessarily scans every car in view, just as human officers 

would in attempting to identify a stolen vehicle. The fact that non-hot list vehicles are 

necessarily checked does not mean there was no investigation. (See fn. 6, post.)

Lastly, Petitioners emphasize the volume and retention of plate scan data to 

highlight the differences between ALPR scans and more traditional investigative 

techniques. In Petitioners’ view, because Real Parties’ ALPR systems each generate 

more than a million system-wide scans each week, and retain data from these scans for 

two to five years, they “do not conduct investigations; they collect data.”

There are two problems with this argument. We have already discussed the first—

the ALPR systems are not merely recording data; rather, Real Parties have deployed these 

systems primarily to detect and locate vehicles that have been connected to a suspected 

crime. The fact that ALPR technology generates substantially more records than an 

officer could generate in manually performing the same task does not mean the ALPR 

plate scans are not records of investigations.6

 

6

For instance, setting practical considerations aside, Real Parties could 

hypothetically deploy human patrol units to photograph every license plate they pass 

during a specific period on a specific route in order to later compare those photographs 

against a hot list of license plates associated with suspected crimes. Though this tactic 

would generate a massive number of license plate photographs, of which very few could 

be expected to appear on the hot list, no one could claim these photographs, and the 

associated time and location data logged by the officers, were not records of the 

investigations these officers performed. The fact that the ALPR system automates this 

process and generates exponentially more records than officers could humanly produce 

has no bearing on whether those plate scans and associated data are records of 

investigations under section 6254, subdivision (f).
13

Second, though ALPR data is retained for two to five years after the initial hot list 

check, this does not strip an investigative record of its exempt status under section 6254, 

subdivision (f). As our Supreme Court explained in Williams, “nothing [in the statute’s 

language] purports to place a time limit on the exemption for investigative files.” 

(Williams, supra, 5 Cal.4th at p. 357.) Records generated by the ALPR system for the 

purpose of locating automobiles associated with a suspected crime, like the investigative 

files discussed in Williams, continue to meet the applicable statutory definition even after 

the investigations for which they were created conclude—that is, they continue to be 

“[r]ecords of . . . investigations conducted by . . . any state or local police agency.” 

(§ 6254, subd. (f); see Williams, at p. 357.) Thus, for our purposes in interpreting the 

exemption, it is of no moment that Real Parties retain the records in a database for years 

after the initial hot list check. 

To be sure, the automated nature of the ALPR system, with its capacity to capture 

and record millions of plate scans throughout Los Angeles City and County, sets it apart 

from the traditional investigatory techniques that courts have considered in earlier cases 

addressing the scope of the investigative records exemption. But that distinction is 

irrelevant to the question of whether the ALPR system’s core function is to “uncover[ ] 

information surrounding the commission of the violation [of law] and its agency”—i.e., 

to investigate suspected crimes. (Haynie, supra, 26 Cal.4th at p. 1071.). We conclude 

that it is, and that the records generated in the course of performing that function are 

records of these investigations. The investigative records exemption applies and shields 

the plate scan data from disclosure under the CPRA.

Because we conclude the exemption under section 6254, subdivision (f) supports

Real Parties’ decision to withhold the ALPR plate scan data, we do not address whether 

Real Parties also met their burden under section 6255’s catchall exemption.
14

DISPOSITION

The petition for writ of mandate is denied. Real Parties are entitled to recover 

their costs in this writ proceeding.

CERTIFIED FOR PUBLICATION

KITCHING, Acting P. J.

We concur:

ALDRICH, J.

EGERTON, J.*

 

*

Judge of the Los Angeles Superior Court, assigned by the Chief Justice pursuant to 

article VI, section 6 of the California Constitution.