Hawaii
Weird Laws in Hawaii: Which Are Still on the Books?
Independently fact-checked against primary sources (last audited October 21, 2026). · 2 primary sources cited on this page. How we verify our legal content
We checked three claims from popular weird-law lists about Hawaii against the Hawaii Revised Statutes, the Department of Agriculture's import rules and, for the claim that names an island, the Kaua'i County Code, as of October 21, 2026. Two of the three claims are state law still on the books. The third points to a real Kaua'i County zoning rule, but the rule is written in stories and feet, not palm trees. For other states, see our weird laws by state guide.
Weird laws in Hawaii: the verdicts
Each claim below was checked against the Hawaii code and, where it names a town, the local code. 3 claims checked.
The claim: Billboards are banned.
What the law says: Hawaii law bars erecting, maintaining or using a billboard or other outdoor advertising device, with a list of exceptions (official notices, on-premises business signs, for-sale signs, etc.). A violation carries a fine of $25 to $500, up to one month in jail, or both. Outdoor advertising that violates the highway outdoor-advertising rules in HRS chapter 264 is also a public nuisance (HRS § 264-76).
“No person shall erect, maintain, or use a billboard or display any outdoor advertising device, except as provided in this section”
Penalty: HRS § 445-121(a): 'Any person violating any provision of sections 445-111 to 445-121 shall be fined not less than $25 nor more than $500, or imprisoned not more than one month, or both.' Injunction suits are also available under § 445-120.
No court opinion in our database cites this section.
Primary source · Checked October 21, 2026.
The claim: Buildings on Kauai may not be taller than a palm tree.
What the law says: Kaua'i does not tie building height to palm trees. Its county zoning code sets numeric limits: a house in a residential district may not be more than two stories above grade, 20 feet to the highest wall plate line, or 30 feet to the highest point of the roof (Kaua'i County Code § 8-4.5). Multi-family buildings, hotels and motels in residential districts are capped at four stories and 40 feet to the wall plate line. The 'no taller than a palm tree' version is popular shorthand for these numeric caps.
Primary source · Checked October 21, 2026.
The claim: Owning a ferret is illegal.
What the law says: Hawaii's Department of Agriculture, acting under the state plant and animal quarantine law (HRS ch. 150A) and its import rules (HAR ch. 4-71), lists ferrets among the animals that private individuals may not bring into or keep in the state.
“No person shall transport, receive for transport, or cause to be transported to the State ... (3) ... any other animal ... that is detrimental or potentially harmful to agriculture, horticulture, animal or public health, or natural resources ... as determined by the board”
Primary source · Checked October 21, 2026.
Checked October 21, 2026. This is legal history and information, not legal advice. Laws change; the linked official text is the authority.
A state without billboards
Hawaii's billboard ban is real and it is statewide. HRS § 445-112 opens:
No person shall erect, maintain, or use a billboard or display any outdoor advertising device, except as provided in this section
The exceptions the section lists include official notices, on-premises business signs and for-sale signs. Under HRS § 445-121(a), anyone violating sections 445-111 to 445-121 shall be fined not less than $25 nor more than $500, or imprisoned not more than one month, or both, and § 445-120 makes injunction suits available as well.
A second statute reaches roadside signs from another direction. Outdoor advertising that violates the highway outdoor-advertising rules in HRS chapter 264 is a public nuisance under HRS § 264-76.
Ferrets and the quarantine law
The ferret claim is also true. Hawaii's Department of Agriculture lists ferrets among the animals that private individuals may not bring into or keep in the state, acting under the plant and animal quarantine law, HRS chapter 150A, and its import rules in Hawaii Administrative Rules chapter 4-71.
The statute itself does not name ferrets. HRS § 150A-6 states the general power the lists rest on:
No person shall transport, receive for transport, or cause to be transported to the State ... (3) ... any other animal ... that is detrimental or potentially harmful to agriculture, horticulture, animal or public health, or natural resources ... as determined by the board
The animal lists that name ferrets come from the department's import rules under that law.
Kaua'i's height limits, in feet
No Kaua'i rule ties building height to palm trees. The county's zoning code sets numeric caps instead. Under Kaua'i County Code § 8-4.5(b), a house in a residential district may be no more than two stories above grade, 20 feet to the highest wall plate line, or 30 feet to the highest point of the roof.
Multi-family buildings, hotels and motels in residential districts are capped at four stories and 40 feet to the wall plate line. The palm tree version is popular shorthand for these numeric caps.
Frequently Asked Questions
Are billboards illegal in Hawaii?
Yes, as a general rule. HRS § 445-112 bars erecting, maintaining or using a billboard or displaying an outdoor advertising device, except as the section provides, with exceptions such as official notices, on-premises business signs and for-sale signs. Violations carry a fine of $25 to $500, up to one month in jail, or both, under HRS § 445-121(a).
Is it illegal to own a ferret in Hawaii?
Hawaii’s Department of Agriculture lists ferrets among the animals that private individuals may not bring into or keep in the state, under the plant and animal quarantine law (HRS ch. 150A) and its import rules (HAR ch. 4-71).
Can buildings on Kauai be taller than a palm tree?
The Kaua’i County Code does not tie building height to palm trees. It caps a house in a residential district at two stories above grade, 20 feet to the highest wall plate line or 30 feet to the highest point of the roof, and caps multi-family buildings, hotels and motels in residential districts at four stories and 40 feet to the wall plate line.
What are some weird laws in Hawaii?
Claims from popular weird-law lists include the billboard ban, the ferret ban and the rule that Kaua’i buildings may not be taller than a palm tree. The first two are state law still on the books; the third is a county zoning rule expressed in stories and feet.
Updates
Independently fact-checked against the cited primary sources
Sources and References
- Haw. Rev. Stat. § 445-112, Billboards and outdoor advertising devices (Hawaii State Legislature)(www.capitol.hawaii.gov).gov
- Haw. Rev. Stat. § 150A-6, plant and animal quarantine law (Hawaii State Legislature)(www.capitol.hawaii.gov).gov
- Kaua’i County Code § 8-4.5, Standards of development applicable to all residential development (official code host)(ecode360.com)