Eight hours a night, every night, on a construction site. That was the on-call time at issue in Mendiola v. CPS Security Solutions, Inc. (2015) 60 Cal.4th 833, and the Supreme Court of California held that all of it had to be paid. The Court also ruled that the employer couldn’t exclude eight hours of sleep from the guards’ 24-hour weekend shifts. For employers with overnight or on-call staff, the exposure depends on how much control the company kept over that time.
When is on-call time hours worked in California?
When the employer controls the employee’s time. Wage Order 4, which covers a long list of office and technical occupations that includes security guards, defines “hours worked” as “the time during which an employee is subject to the control of an employer, and includes all the time the employee is suffered or permitted to work, whether or not required to do so,” according to the order posted by the Department of Industrial Relations. The other industry wage orders use the same control language.
That definition has two separate parts. An employee who is actually working is on the clock. But an employee who isn’t working can still be on the clock if the employer’s control is strong enough. In Mendiola, the Court repeated an earlier holding that “an employee who is subject to an employer’s control does not have to be working during that time to be compensated,” and stated that “[t]he level of the employer’s control over its employees . . . is determinative,” according to the opinion.
To measure control, Mendiola drew on factors that earlier courts had used for on-call claims. They include whether the employee had to live on the premises, how far the employee could go, how often calls came and how fast the employee had to respond, whether the employee could trade on-call duty, whether a pager or phone eased the restrictions, and whether the employee actually used the time for personal activities. Courts also ask whether the time was “spent primarily for the benefit of the employer and its business,” as the Court put it.
What happened in Mendiola?
CPS Security placed guards at construction sites overnight and on weekends. The guards lived in small trailers that CPS provided at each site. On weekdays they worked an eight-hour patrol shift and then spent eight hours on call. On weekends they patrolled for 16 hours and spent another eight on call. CPS paid for patrol hours, but it paid for on-call time only when a guard had to investigate a disturbance or was waiting for, or had been denied, a reliever.
The restrictions were heavy. A guard who wanted to leave had to notify a dispatcher and wait for a reliever, and had to stay on site if no reliever was available. Even with a reliever, the guard had to stay within 30 minutes of the site. Children and pets weren’t allowed in the trailers. Neither was alcohol, and adult visitors needed the approval of CPS’s client.
The Court held that “these plaintiffs are entitled to compensation for all on-call hours spent at their assigned worksites under their employer’s control,” according to the opinion. It didn’t matter that guards could keep personal items in the trailers and generally use the on-call hours as they chose. “The fact that guards could engage in limited personal activities does not lessen the extent of CPS’s control,” the Court wrote.
Can an employer exclude sleep time from a 24-hour shift?
Not under Wage Order 4, and not under most other California wage orders. Federal law allows it. Under 29 C.F.R. section 785.22(a), when an employee is on duty for 24 hours or more, “the employer and the employee may agree to exclude bona fide meal periods and a bona fide regularly scheduled sleeping period of not more than 8 hours from hours worked,” as long as the employer provides adequate sleeping facilities and the employee can usually sleep through the night.
CPS argued that California silently adopted that federal rule. The Supreme Court of California rejected the argument. Wage Order 4 “contains no analog to part 785.22,” the Court said, and because the federal rule would “eliminate[] substantial protections to employees,” the Court declined “to import it into Wage Order 4 by implication.” It disapproved a Court of Appeal decision that had let ship crew members agree to unpaid sleep time, and it limited an older ambulance-crew decision to its facts.
The Court pointed out that the Industrial Welfare Commission wrote sleep-time rules into a few wage orders and left them out of the rest. That’s the reason an employer’s industry matters so much here.
| Wage order and employees | Sleep-time rule |
|---|---|
| Order 4 (professional, technical, clerical, mechanical, including guards) | No exclusion of sleep time from a 24-hour shift under Mendiola |
| Order 9, ambulance drivers and attendants on 24-hour shifts | Written agreement can exclude up to three one-hour meal periods and an uninterrupted sleep period of up to eight hours from daily overtime only |
| Order 5, employees with direct responsibility for children in 24-hour residential care | “[t]ime spent sleeping shall not be included as hours worked,” as quoted in Mendiola |
| Order 5, employees required to live on the premises | Hours worked includes “that time spent carrying out assigned duties” |
| Order 4, health care industry employees | Hours worked is read under the Fair Labor Standards Act |
The ambulance exception is narrower than many employers assume, because it reaches only daily overtime and only employees who agreed in writing. Wage Order 9 says the daily overtime rule “shall not apply to ambulance drivers and attendants scheduled for 24-hour shifts of duty who have agreed in writing to exclude from daily time worked not more than three (3) meal periods of not more than one (1) hour each and a regularly scheduled uninterrupted sleeping period of not more than eight (8) hours.” The Mendiola court explained in a footnote that such an employee “would nevertheless receive his or her regular rate of pay for every hour worked as well as overtime for all hours worked over 40 hours in the workweek,” according to the opinion.
Does the federal on-call rule help a California employer?
Only where a wage order adopts it. Federal law treats an employee who is “required to remain on call on the employer’s premises” as working, but not one who is “merely required to leave word at his home” about where to be reached, under 29 C.F.R. section 785.17.
California courts don’t start from the federal answer. Mendiola rejected a separate federal rule for employees who live on the employer’s premises, quoting an earlier holding that “[a]bsent convincing evidence of the IWC’s intent to adopt the federal standard for determining whether time . . . is compensable under state law, we decline to import any federal standard, which expressly eliminates substantial protections to employees, by implication,” according to the opinion.
The health care carve-out is the main exception. Wage Order 4 says that within the health care industry, hours worked means time the employee is suffered or permitted to work, “as interpreted in accordance with the provisions of the Fair Labor Standards Act,” according to the DIR’s posted order. Hospitals and clinics covered by that language have a federal-style argument that other employers don’t.
How do employers defend on-call pay claims?
By showing the employee’s time was really their own. Mendiola is a strong case for employees because the facts were extreme: guards living on site, a 30-minute leash, and no way to leave without a replacement. Most on-call arrangements look different, and the defense is in that difference.
The best facts for an employer are an employee who waits at home, has a reasonable response window, gets few calls, can swap shifts with coworkers, and actually spends the time on personal activities. An employee who attends a child’s soccer game while carrying a phone is in a different position from a guard who can’t leave a trailer. Phone records, call logs, and the employee’s own testimony about how they spent on-call nights often decide these cases.
The weak facts are the reverse. A short response deadline, a rule against drinking or traveling, frequent call-outs, and discipline for slow responses all point toward control. Employers shouldn’t expect a written policy calling the time “off duty” to carry much weight if the actual rules say otherwise.
Employers with live-in or overnight staff covered by Wage Order 4 should assume sleep time is paid unless a lawyer has confirmed that another wage order applies. The Court refused CPS’s request to apply its ruling only going forward. “The general rule that judicial decisions are given retroactive effect is basic in our legal tradition,” the Court said, quoting an earlier decision. The decision itself was limited, though. The Court expressed “no opinion as what may be required in other circumstances regulated by other wage orders,” which leaves room to argue industry-specific rules.
Unpaid on-call hours also carry overtime consequences. If eight hours of on-call time are added to an eight-hour patrol shift, the employee has worked 16 hours that day, and the daily overtime and double-time rules apply to the hours past eight and 12. Plaintiffs usually add wage statement, waiting time, and PAGA claims on top.
First moves when a claim targets on-call or sleep time
On-call claims usually turn on the actual restrictions the employee lived under, so the early work is collecting proof of how the time was used. The firm’s page on California wage and hour defense has more on how these claims are handled.
- Preserve the on-call policies and schedules, call-out and dispatch logs, response-time rules, time and payroll records, phone and pager records, and the emails and texts of the supervisors who managed on-call coverage.
- Calendar the response deadline on the demand letter, PAGA notice, or complaint, and check for an arbitration agreement and an EPLI policy that requires prompt notice.
- Identify the supervisors and dispatchers who know how on-call duty actually worked, and avoid any change in the claimant’s schedule or duties that could look like retaliation.
- Confirm which wage order covers the employees and compare the written on-call rules with the restrictions employees followed in practice.
- Get legal advice before changing the on-call program, paying back wages, or responding to the claim, since each of those steps can affect class and PAGA exposure.
On-call and overnight shift questions
Does an employee on call at home have to be paid?
Not always. Under Mendiola, the question is how much control the employer kept. An employee who can stay home or go out, answers occasional calls, and has a reasonable time to respond is in a much stronger position for the employer than one who must stay near the worksite. Short response deadlines, frequent call-outs, and limits on travel or alcohol move the time toward compensable.
Can a written agreement exclude sleep time from a 24-hour shift?
Only where a wage order allows it. Mendiola held that Wage Order 4 doesn’t permit excluding sleep time from 24-hour shifts. Wage Order 9 lets ambulance drivers and attendants agree in writing to exclude a sleep period from daily overtime, and Wage Order 5 has its own rules for some residential employees. Outside those provisions, an agreement modeled on the federal rule is a weak defense.
Does Mendiola apply only to security guards?
The holding interpreted Wage Order 4, which covers many occupations beyond guards. The control test it applied comes from the definition of hours worked used across most wage orders, so plaintiffs cite it for on-call claims in many industries. The Court expressly left open what other wage orders require for sleep time, which gives employers in other industries an argument worth making.
Are health care workers treated differently?
Often. Wage Order 4 says hours worked in the health care industry is read under the Fair Labor Standards Act, and federal rules for on-call and sleep time are more favorable to employers. Whether a facility falls within the order’s definition of the health care industry is the first question in any hospital or clinic on-call claim.
If your company faces a claim over on-call or overnight hours
If your company has received a demand letter, PAGA notice, or class action complaint alleging unpaid on-call or sleep time, the rules employees actually followed during those hours usually decide how much of the claim holds up. Rosenberger + Kawabata represents employers defending employment lawsuits and claims through its business litigation practice, including claims involving unpaid on-call time and 24-hour shifts. Contact Rosenberger + Kawabata online for a confidential consultation, or call (310) 894-6921.
Sources
The wage orders are IWC Wage Order 4 and IWC Wage Order 9. The federal regulations are 29 C.F.R. section 785.17 and 29 C.F.R. section 785.22. The decision is Mendiola v. CPS Security Solutions, Inc. (2015) 60 Cal.4th 833.
This post is general information about California and federal employment law as of November 7, 2026. It is not legal advice, and reading it does not create an attorney-client relationship. Employment statutes, regulations, and court decisions change often, and the outcome of any claim depends on its facts. Past results do not guarantee future outcomes.