¶1
Sanders, J.On February 24, 2001, registered sex offender Joseph Rosenow raped and murdered Jennie Mae Osborn. Osborn’s parents sued Mason County for failing to warn them of Rosenow’s presence. The superior court denied Mason County’s motion for summary judgment. The Court of Appeals, Division Two, affirmed the superior court, holding Mason County had a duty to warn the Osborns of Rosenow’s presence under the rescue doctrine. We hold that Mason County had no duty to warn the Osborns because they did not rely on a promise to warn and Jennie Mae Osborn was not a foreseeable victim. Accordingly, we reverse the Court of Appeals and grant Mason County’s motion for summary judgment.
*21FACTS AND PROCEDURAL HISTORY
¶2 Neither party disputes the tragic facts of this case. Rosenow was a registered sex offender. In 1993, he pleaded guilty to third degree rape of a woman at knifepoint, and in 1999 he pleaded guilty to second degree assault for choking unconscious a former sexual partner. When Rosenow was released from prison in Jame 2000 he moved to Hoodsport, Mason County. The prison preliminarily classified Rosenow a level II sex offender, but Mason County reclassified him a level III sex offender.1
¶3 Detective Jason Dracobly handled sex offender registration and community notification for the Mason County Sheriff’s Department.2 Before Rosenow’s release, Shannyn Wiseman, a resident of Mason County, contacted Dracobly, who said he would post flyers and otherwise notify the commomity of Rosenow’s presence. Dracobly registered Rosenow and posted a notice identifying him as a sex offender on Mason County’s website but did not distribute flyers. Wiseman contacted Dracobly again, informing him that Rosenow had followed two minor children, reporting Rosenow’s change of address, and asking whether Dracobly still intended to distribute flyers. Dracobly told her he was too busy to distribute flyers and discouraged her from doing so herself. In December 2000 Rosenow moved from Hoodsport to Shelton. But on February 24, 2001, he returned to Hoodsport where he raped and murdered Osborn.
¶4 Osborn’s parents sued Mason County for failing to warn them of Rosenow’s presence. Mason County moved for summary judgment, arguing that the sex offender statute then in effect, former RCW 4.24.550 (1998), imposed no duty to warn and conferred immunity from liability for failure to warn and moreover no duty to warn existed under *22the public duty doctrine.3 The trial court denied Mason County’s motion for summary judgment, finding former RCW 4.24.550 imposed an implied duty to warn. The Court of Appeals granted Mason County’s motion for discretionary review and affirmed the trial court’s ruling on different grounds. It found no duty to warn under former RCW 4.24.550, but held Mason County might have had a duty to warn under the rescue doctrine. Osborn v. Mason County, 122 Wn. App. 823, 95 P.3d 1257 (2004). We granted Mason County’s petition for review. We hold Mason County had no statutory or common law duty to warn the Osborns of Rosenow’s presence and remand to the trial court with directions to grant Mason County’s cross-motion for summary judgment.
STANDARD OF REVIEW
f 5 A motion for summary judgment presents a question of law reviewed de novo. See Denaxas v. Sandstone Court of Bellevue, L.L.C., 148 Wn.2d 654, 662, 63 P.3d 125 (2003). We construe the evidence in the light most favorable to the nonmoving party, Folsom v. Burger King, 135 Wn.2d 658, 663, 958 P.2d 301 (1998), and grant summary judgment if “there is no genuine issue as to any material fact” and “the moving party is entitled to a judgment as a matter of law.” CR 56(c).
ANALYSIS
¶6 This case presents a question of law: did Mason County have a duty to warn the Osborns of Rosenow’s presence? Puzzlingly, the Court of Appeals denied summary judgment because “the Osborns have asserted facts from which a trier of fact could find that Mason County’s actions affirmatively created a separate duty under the rescue *23doctrine.” Osborn, 122 Wn. App. at 837. But, of course, the “existence of duty is a question of law,” not a question of fact. Tae Kim v. Budget Rent A Car Sys., Inc., 143 Wn.2d 190, 195, 15 P.3d 1283 (2001). And neither party disputes any fact relevant to the existence of a duty. Rather, as the Court of Appeals recognizes, these parties dispute only whether Mason County’s actions “negligently increased the risk of harm to Rosenow’s potential victims.” Osborn, 122 Wn. App. at 835. So, presumably, the Court of Appeals meant the Osborns have asserted facts sufficient for a jury to find Mason County breached a duty to warn under the rescue doctrine.
I. Mason County Had No Duty To Warn the Osborns of Rosenow’s Presence
¶7 But the Osborns do not assert facts sufficient to show Mason County had a duty to warn them of Rosenow’s presence because they do not claim they relied on Mason County’s assurances. A duty exists under the rescue doctrine only if an injured party reasonably relies on the assurances of a negligent rescuer. The Court of Appeals held Mason County had a duty to warn the Osborns under the rescue doctrine because Dracobly assured Wiseman he would post flyers, failed to post flyers, and discouraged Wiseman from posting flyers. Id. In other words, it held Mason County had a duty to warn the Osborns because Wiseman relied on its assurances. But that cannot support a duty under the rescue doctrine unless the Osborns reasonably relied on Wiseman. And the Osborns fail to show such reliance. Because Mason County had no duty to warn the Osborns — under the rescue doctrine or any other theory of liability — it is entitled to summary judgment.
A. Mason County Had No Statutory Duty To Warn the Osborns
¶8 The Court of Appeals correctly rejected the superior court’s conclusion former RCW 4.24.550 created an implied duty to warn of the presence of a sex offender. *24Clerk’s Papers at 316-17. Its conclusion follows inexorably from the plain language of the statute: “Except as may otherwise be provided by law, nothing in this section shall impose any liability upon a public official, public employee, or public agency for failing to release information authorized under this section.” Former RCW 4.24.550(6). Thus, former RCW 4.24.550 neither imposed a duty to warn nor conferred immunity from liability for failure to warn.
B. Mason County Had No “Take Charge” Duty To Warn the Osborns
¶9 Under the “special relationship” doctrine, a public entity has a duty to control persons it has authority to control and a duty to protect foreseeable victims of dangerous persons leaving its custody. See, e.g., Joyce v. Dep’t of Corr., 155 Wn.2d 306, 315-16, 119 P.3d 825 (2005). In other words, a public entity “has a duty to take reasonable precautions to protect against reasonably foreseeable dangers.” Taggart v. State, 118 Wn.2d 195, 217, 822 P.2d 243 (1992).
¶10 Accordingly, a public entity has a “take charge” duty to control parolees, id., mental patients, Petersen v. State, 100 Wn.2d 421, 428-29, 671 P.2d 230 (1983), and others it has authority to control, to the extent it has authority to control them. See, e.g., Couch v. Dep’t of Corr., 113 Wn. App. 556, 571, 54 P.3d 197 (2002) (holding authority to control limits duty to control). And a public entity has a duty to protect foreseeable victims of criminals, mental patients, and others leaving its custody. See Petersen, 100 Wn.2d at 428-29. See also Doyle v. United States, 530 F. Supp. 1278, 1288 (C.D. Cal. 1982) (holding “a duty to warn arises only when the potential victim is known and foreseeable”); Hoff v. Vacaville Unified Sch. Dist., 19 Cal. 4th 925, 937, 968 P.2d 522, 80 Cal. Rptr. 2d 811 (1998) (holding “public entities have no affirmative duty to warn of the release of an inmate with a violent history unless the inmate makes a specific threat against a specific, identifiable victim or group of victims”); Thompson v. County of Alameda, 27 Cal. 3d 741, *25754, 614 P.2d 728, 167 Cal. Rptr. 70 (1980) (finding “no affirmative duty to warn of the release of an inmate with a violent history who has made nonspecific threats of harm directed at nonspecific victims” (emphasis omitted)). But Mason County did not “take charge” of Rosenow because it had no authority to control him. And it had no “special relationship” duty to warn the Osborns because Jennie Mae Osborn was not a foreseeable victim of Rosenow.
C. Mason County Had No Duty To Warn the Osborns under the Rescue Doctrine
¶11 Nor does the rescue doctrine apply because the Osborns did not rely on Mason County’s assurances. The Court of Appeals mistakenly concluded reliance “is not a necessary element” of the rescue doctrine, holding Mason County had a duty to warn because it increased Osborn’s risk of injury by promising to warn, failing to warn, and discouraging a third party from warning. Osborn, 122 Wn. App. at 835. On the contrary, reliance is the linchpin of the rescue doctrine.
f 12 Under the rescue doctrine, a public entity has a “special” duty “to exercise reasonable care after assuming a duty to warn or come to the aid of a particular plaintiff.” Bailey v. Town of Forks, 108 Wn.2d 262, 268, 737 P.2d 1257, 753 P.2d 523 (1987). That “special” duty exists because a public entity’s assurances may induce reliance. “A person who voluntarily promises to perform a service for another in need has a duty to exercise reasonable care when the promise induces reliance and causes the promisee to refrain from seeking help elsewhere.” Folsom, 135 Wn.2d at 676. See also Couch, 113 Wn. App. at 572 n.66 (finding no duty under rescue doctrine without reliance). And see Restatement (Second) of Torts § 323, cmt. d (1965) (“There is no essential reason why the breach of a promise which has induced reliance and so caused harm should not be actionable in tort.”). Cf. Bd. of Regents v. Roth, 408 U.S. 564, 92 S. Ct. 2701, 33 L. Ed. 2d 548 (1972) (holding due process protects reasonable reliance on assurances of public entity). *26A person may reasonably rely on explicit or implicit assurances. “Even where an offer to seek or render aid is implicit and unspoken, a duty to make good on the promise has been found by most courts if it is reasonably relied upon.” Brown v. MacPherson’s, Inc., 86 Wn.2d 293, 301, 545 P.2d 13 (1975). But the Osborns do not claim Mason County promised to warn them of Rosenow’s presence.
¶13 A public entity also has a duty under the rescue doctrine when an injured party reasonably relies on a third party that “refrains from acting” as a result of the public entity’s assurances. Chambers-Castanes v. King County, 100 Wn.2d 275, 286 n.3, 669 P.2d 451 (1983). See also Brown, 86 Wn.2d at 301 (holding “a duty to act” is “created by reliance not by the person to whom the aid is to be rendered, but by another who, as a result of the promise, refrains from acting on that person’s behalf”); Meneely v. S.R. Smith, Inc., 101 Wn. App. 845, 859-60, 5 P.3d 49 (2000) (holding trade association “voluntarily assumed the duty to warn” because “manufacturers relied upon” assurances). So, in Brown, a duty existed because the injured parties reasonably relied on their broker to warn them of danger, a public entity promised a third party it would warn the injured parties of danger, and the public entity caused the broker to believe no danger existed. 86 Wn.2d at 301-02. And in Meneely, a duty existed because the injured parties relied on a manufacturer to warn them of danger, a trade association promulgated “industry wide safety standards,” and the manufacturer relied on the safety standards. 101 Wn. App. at 857-62. No duty can exist under the rescue doctrine without this privity of reliance.
¶14 In sum, a public entity has a duty under the rescue doctrine when an injured party reasonably relies, or is in privity with a third party that reasonably relies, on its promise to aid or warn. See, e.g., Bratton v. Welp, 145 Wn.2d 572, 576-77, 39 P.3d 959 (2002); Babcock v. Mason County Fire Dist. No. 6, 144 Wn.2d 774, 778, 30 P.3d 1261 (2001) (finding no duty to aid because reliance was unreasonable); Beal v. City of Seattle, 134 Wn.2d 769, 785, 954 P.2d 237 *27(1998) (analyzing duty to aid under “special relationship” doctrine); Honcoop v. State, 111 Wn.2d 182, 192-93, 759 P.2d 1188 (1988) (holding duty to warn exists only if public entity makes “assurances that could give rise to justifiable reliance”). But the Osborns relied on neither Mason County nor Wiseman to warn them of Rosenow’s presence. Accordingly, Mason County had no duty to warn the Osborns under the rescue doctrine.
II. This Case Does Not Implicate the Public Duty Doctrine
¶15 The Osborns urge us to abandon the “public duty” doctrine. But no public duty doctrine analysis is necessary because Mason County had no duty to warn the Osborns of Rosenow’s presence. “We have almost universally found it unnecessary to invoke the public duty doctrine to bar a plaintiff’s lawsuit.” Bailey, 108 Wn.2d at 266. And this case is no exception.
¶16 A cause of action for negligence exists only if “the defendant owes a duty of care to plaintiff.” Chambers-Castanes, 100 Wn.2d at 284. Accordingly, under the public duty doctrine, a public entity has a duty of care when it owes a duty “to the injured plaintiff,” but does not have a duty of care when it owes a duty “to the public in general.” Babcock, 144 Wn.2d at 785. We often paraphrase this “basic principle of negligence law” as “a duty to all is a duty to no one.” Id.
¶17 Because a public entity is liable in tort “to the same extent as if it were a private person or corporation,” former RCW 4.92.090 (1963) (state) and former RCW 4.96.010 (1967) (municipality), the public duty doctrine does not— cannot — provide immunity from liability. Rather, it is a “ ‘focusing tool’ ” we use to determine whether a public entity owed a duty to a “ ‘nebulous public’ ” or a particular individual. Taylor v. Stevens County, 111 Wn.2d 159, 166, 759 P.2d 447 (1988) (quoting J&B Dev. Co. v. King County, 100 Wn.2d 299, 304-05, 669 P.2d 468 (1983)). The public duty doctrine simply reminds us that a public entity — like *28any other defendant — is liable for negligence only if it has a statutory or common law duty of care. And its “exceptions” indicate when a statutory or common law duty exists. “The question whether an exception to the public duty doctrine applies is thus another way of asking whether the State had a duty to the plaintiff.” Taggart, 118 Wn.2d at 218. See also Bishop v. Miche, 137 Wn.2d 518, 530, 973 P.2d 465 (1999) (“Exceptions to the doctrine generally embody traditional negligence principles and may be used as focusing tools to determine whether a duty is owed.”). In other words, the public duty doctrine helps us distinguish proper legal duties from mere hortatory “duties.”
¶18 Assuredly, Mason County has a “duty” to protect its citizens in a colloquial sense, but it does not have a legal duty to prevent every foreseeable injury. See Thompson, 27 Cal. 3d at 753. An “action for negligence does not lie unless the defendant owes a duty of care to the plaintiff,” Bailey, 108 Wn.2d at 266, and “a broad general responsibility to the public at large rather than to individual members of the public” simply does not create a duty of care. Campbell v. City of Bellevue, 85 Wn.2d 1, 9, 530 P.2d 234 (1975). Under the rescue doctrine, both public, Brown, 86 Wn.2d at 301, and private, Meneely, 101 Wn. App. at 860, entities have a duty to warn those who reasonably rely on a promise to warn. But no duty to warn exists under the rescue doctrine without reasonable reliance on such a promise.
¶19 And so, the facts as presented by the Osborns cannot support a duty to warn under the rescue doctrine. They contend Mason County had a duty to warn them of Rosenow’s presence under the rescue doctrine because Dracobly promised to warn the community, failed to warn the community, and discouraged Wiseman from warning the community. But no general duty to warn exists “in the absence of a known danger to a specific individual” because there is no basis on which to warn anyone. Sharpe v. Dep’t of Mental Health, 292 S.C. 11, 19, 354 S.E.2d 778 (1987). *29See also Thompson, 27 Cal. 3d at 754-55 (“Notification to the public at large of the release of each offender who has a history of violence and who has made a generalized threat at some time during incarceration or while under supervision would, in our view, produce a cacophony of warnings that by reason of their sheer volume would add little to the effective protection of the public.”); VanLuchene v. State, 244 Mont. 397, 403, 797 P.2d 932 (1990) (“The merit of issuing a warning to the general public in the instant case is equally questionable. Appellants do not set forth how their actions would have differed had respondent made a general public warning.”); Mangeris v. Gordon, 94 Nev. 400, 403, 580 P.2d 481 (1978) (“In such circumstances, the defendant is impressed with a duty to warn foreseeable victims of foreseeable harm.”); Melinda K. Blatt, Comment, State Liability for Injuries Inflicted by Parolees, 56 U. Cin. L. Rev. 615, 635 (1987) (finding “no duty to provide a warning of the release of a dangerous prisoner to the public at large”). The Osborns do not allege that Dracobly “engaged in conduct within the scope of employment that would render” him liable for their daughter’s death, and “there is no basis for imposing vicarious liability upon” Mason County. Zelig v. County of Los Angeles, 27 Cal. 4th 1112, 1130-31, 45 P.3d 1171, 119 Cal. Rptr. 2d 709 (2002). Mason County is not liable for failing to warn the Osborns of Rosenow’s presence — with or without the public duty doctrine — simply because it had no statutory or common law duty to warn them.
CONCLUSION
¶20 We reverse the Court of Appeals and grant Mason County’s motion for summary judgment. The Osborns fail to assert facts sufficient to show Mason County had a duty to warn them of Rosenow’s presence.
Alexander, C.J., and Madsen, Bridge, Owens, Fairhurst, and J.M. Johnson, JJ., concur.
Level I sex offenders are low risk reoffenders, level II are moderate risk, and level III are high risk. RCW 72.09.345(5).
Former RCW 9A.44.130 (2000) required counties to record the name, address, date and place of birth, criminal convictions, dates and places of conviction, aliases, Social Security number, photograph, and fingerprints of released sex offenders.
In 2000, the “state’s policy” was “to authorize the release of necessary and relevant information about sexual predators to members of the general public.” Laws of 1990, ch. 3, § 116. A 2001 amendment requires county sheriffs to publish a notice in a newspaper of general circulation when a level III sex offender moves to their jurisdiction. See RCW 4.24.550(4); Laws of 2001, ch. 283, § 2.