Illinois Dog Bite Law

How dog bite liability works in Illinois

Illinois dropped the one-bite rule for dogs in 1949. The Supreme Court described the purpose of that first statute in Harris v. Walker, 119 Ill. 2d 542 (1988), as easing the burden on bite victims by removing the need to prove the owner knew the dog was dangerous². Today the rule sits in 510 ILCS 5/16 and covers any animal, not only dogs, and any attack, attempted attack or injury, not only bites¹.

Illinois judges nonetheless insist the Act is not absolute. They read four elements into it: an injury caused by the defendant's animal, no provocation, peaceable conduct by the injured person, and presence where that person had a right to be⁷. The dog must also do something: a dog lying still in a road was not enough in Coe v. Lewsader, 2016 IL App (4th) 150841⁷. And someone who has the dog in their care counts as an "owner", which cuts both ways, as the defenses below show^1,8.

What the Act takes away is the defendant's favorite argument in an ordinary injury case. In Johnson v. Johnson, 386 Ill. App. 3d 522 (2008), the First District held that comparative negligence is not a defense to an Animal Control Act claim; the injured person's conduct matters only if it provoked the animal⁶. Provocation is a complete bar, though, and Illinois courts count accidental provocation, even by a toddler⁶.

Illinois also bans breed discrimination twice: local animal rules may not be breed-specific, and since December 2023 home and renters insurers may not refuse or surcharge a policy because of a dog's breed^1,14. See how this compares with Indiana, Wisconsin and the national table.

The Illinois dog bite statute

If a dog or other animal, without provocation, attacks, attempts to attack, or injures a person who is peaceably conducting themselves in any place where they may lawfully be, the owner is liable in civil damages for the full amount of the injury proximately caused¹. "Owner" includes anyone with a property right in the animal, anyone who keeps or harbors it, has it in their care or acts as its custodian, and anyone who knowingly permits a dog to remain on premises they occupy¹. The injured person does not have to prove the dog was vicious or that the owner knew it⁹.

• Law: 510 ILCS 5/16 (Animal Control Act, Section 16 (Animal attacks or injuries)), enacted 1949; last changed 2006 (P.A. 94-819)
• Injuries covered: Any injury the dog causes (bites, knock-downs, chases)
• Where: Public places, or lawfully on private property
• Who is liable: The owner, or a keeper or harborer
• Damages: All damages, under the ordinary rules

Other ways to prove liability

The Act did not abolish the older common-law claims, so a plaintiff can plead both⁸. At common law, the owner of a domestic animal is liable only after proof that the animal had a dangerous disposition the owner knew about⁶. A negligence claim against someone who is not an "owner" under the Act, such as a landlord, turns on control and knowledge¹⁰. Plaintiffs usually prefer the Act because it needs no proof of knowledge or carelessness and comparative fault does not apply to it^6,9.

Defenses owners raise

Provocation

No recovery under the Act if the animal was provoked. Provocation can be unintentional: Illinois pattern instructions define it as any act, intentional or not, that would reasonably be expected to make a normal animal react as this one did, and a 2½-year-old who stepped on a dog's tail was held to have provoked it⁶.

Trespassing

The Act protects only a person who is in a place where they may lawfully be and who is behaving peaceably; a trespasser, or someone attacking the owner, falls outside it^1,7. A common-law claim may remain, but it requires proof of the owner's knowledge or negligence⁸.

Assumption of risk

In Harris v. Walker the Supreme Court held that a person who rents a horse and expressly accepts the risks cannot sue under the Act². Appellate courts apply the same idea to anyone who invites or explicitly assumes the risk that the animal will injure them⁶.

Veterinarians and dog professionals

Because anyone who has the animal in their care is an "owner", courts ask whether an injured handler was in control of the dog^1,8. In Hayes v. Adams, 2013 IL App (2d) 120681, a dog's legal owner was not liable when a veterinary clinic let the dog escape and it bit a child; the clinic had care, custody and control⁸.

Police dogs

Section 16 has no police-dog exception. In Wilson v. City of Decatur, 389 Ill. App. 3d 555 (2009), a city that owned a police dog was held liable under the Act, and the Tort Immunity Act did not shield it¹¹. The one-year deadline for suits against local governments still applies¹².

Other defense

The animal must make some overt move toward the injured person; a dog passively lying in a road did not trigger the Act⁷. Local governments that allow dog parks are immune from claims for incidents there except for willful and wanton misconduct¹.

Shared fault

Modified comparative fault (barred at 51%) (735 ILCS 5/2-1116).

In negligence claims, a plaintiff more than 50% at fault recovers nothing, and a lower share reduces the award proportionally⁵. That statute does not reach Animal Control Act claims: Johnson v. Johnson held that comparative negligence is not a defense under the Act, that the plaintiff's conduct counts only as provocation, and that a parent's negligent supervision is irrelevant⁶. The Fourth District was asked in 2016 whether Johnson controls every Act case but did not answer, and the Supreme Court has not ruled⁷.

How the five fault systems compare: provocation, trespass and shared fault.

Illinois dog bite statute of limitations

2 years (735 ILCS 5/13-202)

A personal-injury suit must be filed within 2 years after the cause of action accrued, normally the day of the bite³. A suit against a local public entity or its employee, for example over a police dog or a county shelter dog, must be filed within one year¹².

Children. If the bitten person was under 18, the 2 years start on their 18th birthday, so the suit can be filed until age 20⁴.

Work out your own date with the dog bite claim checker, or compare deadlines in every state.

Damages

Section 16 makes the owner liable for "the full amount of the injury proximately caused", which covers medical bills, lost earnings, pain and suffering, scarring and disfigurement¹. The Act sets no cap and no double or treble damages. Punitive damages cannot be requested in the first complaint in a negligence-based injury case; the plaintiff must win a pretrial motion showing a reasonable likelihood of proving facts that support them¹³.

Landlords and property owners

A landlord is not an "owner" just because the lease allows a dog: in Steinberg v. Petta, 114 Ill. 2d 496 (1986), the Supreme Court reversed a judgment against an absentee landlord, holding that harboring or keeping requires some degree of care, custody or control over the animal⁹. In negligence, Klitzka v. Hellios, 348 Ill. App. 3d 594 (2004), holds that a landlord owes no duty to a tenant's guest unless the landlord retained control over the area where the attack happened, and the power to evict the tenant over the dog is not control¹⁰. A landlord who lives on the premises and knowingly lets the dog stay there can be an "owner" under the Act's definition¹.

Insurance

Since December 2023, homeowner's and renter's insurers may not refuse, cancel, surcharge or limit coverage based solely on owning a dog of a particular breed or mix¹⁴. They may still act on an individual dog that has been declared dangerous or vicious under the Animal Control Act¹⁴. State law does not require owners of dangerous or vicious dogs to carry liability insurance¹.

Illinois ranked #8 in the United States for dog-related homeowners insurance claims in 2025: 1,283 claims with an average cost of $79,596 (national average $65,450), according to the Insurance Information Institute and State Farm. These are insurer payouts, not court awards.

More on coverage, breed exclusions and renters policies: dog bite insurance.

Why Illinois courts say the Act is not "strict liability"

National lists put Illinois among the strict-liability states, and the label fits in one sense: section 16 needs no proof that the owner knew the dog was dangerous or was careless^1,9. Illinois judges, however, repeatedly write that the Act "does not impose strict liability upon the owner"⁸. They mean that liability is not a penalty for owning a dog. The Act is read as protecting people who cannot protect themselves from an animal, so it does not help someone who expressly took on the risk, like the horse renter in Harris v. Walker². Nor does it reach a legal owner who had handed the dog to a veterinary clinic, as in Hayes v. Adams⁸, or a dog that only lay in the road⁷. On the other side, the defendant cannot use the plaintiff's ordinary carelessness to reduce the award, because comparative negligence is not a defense to the Act⁶. For the injured person, the practical questions are who had control of the dog and whether anything they did could count as provocation.

Bite reports and quarantine

Anyone who knows that a person has been bitten by an animal must notify the county animal control Administrator within 24 hours¹. The owner must present the animal to a licensed veterinarian within 24 hours, and the veterinarian reports the outcome to the Administrator, who then notifies the bitten person¹. The Illinois Department of Public Health asks that all animal bites be reported to local animal control¹⁵.

The biting animal is confined under a veterinarian's observation for at least 10 days from the bite, until a veterinarian examines and releases it; the Administrator can shorten the period¹. A dog with current rabies vaccination may be confined at home if the Administrator approves¹. At the end, the owner pays for the exam, vaccination, microchip and a $25 public safety fine, and may not hide, sell, give away or euthanize the dog before release¹. Since January 2026, a dog exempted from vaccination for medical reasons is treated as unvaccinated after a bite¹.

Dangerous-dog hearings, euthanasia orders and criminal penalties are covered on Illinois dangerous dog law.

Questions about Illinois dog bite law

Is Illinois a one-bite state?

No. Since 1949 Illinois law has let a person attacked by a dog recover without proving the dog had shown any dangerous tendency². Section 16 of the Animal Control Act requires only an unprovoked attack or injury on a peaceable person who was lawfully where they were^1,7. See the one-bite rule guide for how other states differ.

My child was bitten. Does it matter that the child was teasing the dog?

It can. Illinois counts unintentional provocation, and in Nelson v. Lewis a toddler who stepped on a dog's tail was held to have provoked it⁶. The question is whether a normal dog would react the way this one did, so a mild act followed by a savage attack may not be provocation⁶. Ordinary carelessness that is not provocation does not reduce the award, and a parent's poor supervision is not a defense⁶. The child has until two years after turning 18 to sue⁴.

Can I sue the person who was dog-sitting, not the owner?

Often, yes. The Act's definition of owner includes anyone who keeps or harbors the dog, has it in their care or acts as its custodian¹. Courts look at who had care, custody and control at the time; a legal owner who had left the dog at a veterinary clinic was not liable in Hayes v. Adams⁸.

Can a homeowners insurer in Illinois drop me because of my dog's breed?

Not for breed alone. Since December 2023, 215 ILCS 5/143.10e bars homeowner's and renter's insurers from refusing, cancelling, surcharging or limiting coverage based solely on a dog's breed or mix¹⁴. An insurer can still act if your dog has been declared dangerous or vicious under the Animal Control Act¹⁴. See dog bite insurance.

Will my dog be put down for biting someone in Illinois?

Not automatically. A first bite leads to at least 10 days of observation, and a bite without serious injury can lead to a dangerous-dog finding with sterilization, a microchip and training or supervision orders¹. Euthanasia is possible only after a circuit court finds the dog vicious, and even then it is up to the judge¹. See my dog bit someone.

Official contacts

Sources

1. Animal Control Act, 510 ILCS 5, Illinois General Assembly. Checked 17 October 2026.
2. Harris v. Walker, 119 Ill. 2d 542 (1988), Supreme Court of Illinois (via CourtListener). Checked 17 October 2026.
3. 735 ILCS 5/13-202 (personal injury limitations), Illinois General Assembly. Checked 17 October 2026.
4. 735 ILCS 5/13-211 (minors and persons under legal disability), Illinois General Assembly. Checked 17 October 2026.
5. 735 ILCS 5/2-1116 (limitation on recovery in tort actions), Illinois General Assembly. Checked 17 October 2026.
6. Johnson v. Johnson, 386 Ill. App. 3d 522 (2008), Illinois Appellate Court, First District. Checked 17 October 2026.
7. Coe v. Lewsader, 2016 IL App (4th) 150841, Illinois Appellate Court, Fourth District. Checked 17 October 2026.
8. Hayes v. Adams, 2013 IL App (2d) 120681, Illinois Appellate Court, Second District. Checked 17 October 2026.
9. Steinberg v. Petta, 114 Ill. 2d 496 (1986), Supreme Court of Illinois (via CourtListener). Checked 17 October 2026.
10. Klitzka v. Hellios, 348 Ill. App. 3d 594 (2004), Illinois Appellate Court, Second District (via CourtListener). Checked 17 October 2026.
11. Wilson v. City of Decatur, 389 Ill. App. 3d 555 (2009), Illinois Appellate Court, Fourth District (via CourtListener). Checked 17 October 2026.
12. 745 ILCS 10/8-101 (Tort Immunity Act limitation), Illinois General Assembly. Checked 17 October 2026.
13. 735 ILCS 5/2-604.1 (pleading of punitive damages), Illinois General Assembly. Checked 17 October 2026.
14. 215 ILCS 5/143.10e (home property insurance; dog breeds), Illinois General Assembly. Checked 17 October 2026.
15. Rabies, Illinois Department of Public Health. Checked 17 October 2026.
16. Animal and Rabies Control, Cook County Government. Checked 17 October 2026.