a. For purposes of this section:
(1) The term "bicycle" shall mean a two or three wheeled device upon which a person or persons may ride, propelled by human power through a belt, a chain or gears, with such wheels in a tandem or tricycle, except that it shall not include such a device having solid tires and intended for use only on a sidewalk by a child.
(2) The term "sidewalk" shall mean that portion of the street, whether paved or unpaved, between the curb lines or the lateral lines of a roadway and the adjacent property lines, intended for the use of pedestrians. Where it is not clear which section is intended for the use of pedestrians the sidewalk will be deemed to be that portion of the street between the building line and the curb.
(3) The term "child" shall mean a person less than fourteen years of age.
b. No person shall ride a bicycle upon any sidewalk unless permitted by an official sign. A person who violates this subdivision may be issued a notice of violation and shall be liable for a civil penalty of not more than one hundred dollars which may be recovered in a proceeding before the environmental control board.
c. A person who violates subdivision b of this section in a manner that endangers any other person or property shall be guilty of a misdemeanor, punishable by a fine of not more than one hundred dollars or imprisonment for not more than twenty days or both such fine and imprisonment. Such person shall also be liable for a civil penalty of not less than one hundred dollars nor more than three hundred dollars, except where a hearing officer has determined that where there was physical contact between the rider and another person, an additional civil penalty of not less than one hundred dollars nor more than two hundred dollars may be imposed. Such civil penalties may be recovered in a proceeding before the environmental control board. Enforcement agents shall indicate on the summons or notice of violation issued pursuant to this subdivision whether physical contact was made between the rider and another person. Any person who violates any provision of this subdivision more than once within any six month period shall be subject to the imposition of civil penalties in an amount that is double what would otherwise have been imposed for the commission of a first violation. It shall be an affirmative defense that physical contact between a rider and another person was in no way the fault of the rider.
d. Where a summons or notice of violation is issued for a violation of subdivision c of this section, the bicycle may be seized and impounded.
e. A bicycle impounded pursuant to this section shall be released to the owner or other person lawfully entitled to possession upon payment of the costs of removal and storage as set forth in the rules of the police department and proof of payment of any fine or civil penalty for the violation or, if a proceeding for the violation is pending in a court or before the environmental control board, upon the posting of a bond or other form of security acceptable to the police department in an amount which will assure the payment of such costs and any fine or civil penalty which may be imposed for the violation. If the court or the environmental control board finds in favor of the defendant or respondent, the owner shall be entitled forthwith to possession of the bicycle without charge or to the extent that any amount has been previously paid for release of the bicycle, such amount shall be refunded. The police department shall establish by rule the time within which bicycles which are not redeemed may be deemed abandoned and the procedures for disposal.
f. The owner of a bicycle shall be given the opportunity for a post seizure hearing within five business days before the environmental control board regarding the impoundment. The environmental control board shall render a determination within three business days after the conclusion of the hearing. Where the board finds that there was no basis for the impoundment, the owner shall be entitled forthwith to possession of the bicycle without charge or to the extent that any amount has been previously paid for release of the bicycle, such amount shall be refunded.
g. Upon the impoundment of a bicycle, the rider shall be given written notice of the procedure for redemption of the bicycle and the procedure for requesting a post seizure hearing. Where the rider of a bicycle is not the owner thereof notice provided to the rider shall be deemed to be notice to the owner. Where the defendant or respondent is less than eighteen years old such notice shall also be mailed to the parent, guardian or where relevant, employer of the respondent, if the name and address of such person is reasonably ascertainable.
h. In any proceeding under this section it shall be an affirmative defense that the defendant or respondent was less than fourteen years old at the time the violation was committed.
i. The provisions of this section may be enforced by the police department or designated employees of the department, the department of sanitation, the department of parks and recreation.