Assured Clear Distance Ahead Law & Legal Definition


ACDA or "assured clear distance ahead" requires a driver to keep his motor vehicle under control so that he can stop in the distance in which he can clearly see. Some states, like Ohio, have enacted this rule into statute. Common reasons for receiving an ACDA citation include speeding through a construction zone, driving over 20 miles per hour in a school zone, and other speeding violations on the freeway. ACDA is a two-point violation. Although it is dependent on the facts surrounding the citation, ACDA is usually classified as a minor misdemeanor. However, a citation for ACDA can have serious consequences, especially if a driver has been convicted of previous offenses or was cited for multiple violations. The Ohio statute reads in its relevant part...

§ 4511.21. Speed limits

(A) No person shall operate a motor vehicle, trackless trolley, or streetcar at a speed greater or less than is reasonable or proper, having due regard to the traffic, surface, and width of the street or highway and any other conditions, and no person shall drive any motor vehicle, trackless trolley, or streetcar in and upon any street or highway at a greater speed than will permit the person to bring it to a stop within the assured clear distance ahead.
(B) It is prima-facie lawful, in the absence of a lower limit declared pursuant to this section by the director of transportation or local authorities, for the operator of a motor vehicle, trackless trolley, or streetcar to operate the same at a speed not exceeding the following:
(1) (a) Twenty miles per hour in school zones during school recess and while children are going to or leaving school during the opening or closing hours, and when twenty miles per hour school speed limit signs are erected; except that, on controlled-access highways and expressways, if the right-of-way line fence has been erected without pedestrian opening, the speed shall be governed by division (B)(4) of this section and on freeways, if the right-of-way line fence has been erected without pedestrian opening, the speed shall be governed by divisions (B)(9) and (10) of this section.
(2) Twenty-five miles per hour in all other portions of a municipal corporation, except on state routes outside business districts, through highways outside business districts, and alleys;
(3) Thirty-five miles per hour on all state routes or through highways within municipal corporations outside business districts, except as provided in divisions (B)(4) and (6) of this section;
(4) Fifty miles per hour on controlled-access highways and expressways within municipal corporations;
(5) Fifty-five miles per hour on highways outside municipal corporations, other than highways within island jurisdictions as provided in division (B)(8) of this section and freeways as provided in division (B)(13) of this section;
(6) Fifty miles per hour on state routes within municipal corporations outside urban districts unless a lower prima-facie speed is established as further provided in this section;
(7) Fifteen miles per hour on all alleys within the municipal corporation;
(8) Thirty-five miles per hour on highways outside municipal corporations that are within an island jurisdiction;
(9) Fifty-five miles per hour at all times on freeways with paved shoulders inside municipal corporations, other than freeways as provided in division (B)(13) of this section;
(10) Fifty-five miles per hour at all times on freeways outside municipal corporations, other than freeways as provided in division (B)(13) of this section;
(11) Fifty-five miles per hour at all times on all portions of freeways that are part of the interstate system and on all portions of freeways that are not part of the interstate system, but are built to the standards and specifications that are applicable to freeways that are part of the interstate system for operators of any motor vehicle weighing in excess of eight thousand pounds empty weight and any noncommercial bus;
(12) Fifty-five miles per hour for operators of any motor vehicle weighing eight thousand pounds or less empty weight and any commercial bus at all times on all portions of freeways that are part of the interstate system and that had such a speed limit established prior to October 1, 1995, and freeways that are not part of the interstate system, but are built to the standards and specifications that are applicable to freeways that are part of the interstate system and that had such a speed limit established prior to October 1, 1995, unless a higher speed limit is established under division (L) of this section;
(13) Sixty-five miles per hour for operators of any motor vehicle weighing eight thousand pounds or less empty weight and any commercial bus at all times on all portions of the following:
(a) Freeways that are part of the interstate system and that had such a speed limit established prior to October 1, 1995, and freeways that are not part of the interstate system, but are built to the standards and specifications that are applicable to freeways that are part of the interstate system and that had such a speed limit established prior to October 1, 1995;
(b) Freeways that are part of the interstate system and freeways that are not part of the interstate system but are built to the standards and specifications that are applicable to freeways that are part of the interstate system, and that had such a speed limit established under division (L) of this section;
Rural, divided, multi-lane highways that are designated as part of the national highway system under the "National Highway System Designation Act of 1995," 109 Stat. 568, 23 U.S.C.A. 103, and that had such a speed limit established under division (M) of this section.
(C) It is prima-facie unlawful for any person to exceed any of the speed limitations in divisions (B)(1)(a), (2), (3), (4), (6), (7), and (8) of this section, or any declared pursuant to this section by the director or local authorities and it is unlawful for any person to exceed any of the speed limitations in division (D) of this section. No person shall be convicted of more than one violation of this section for the same conduct, although violations of more than one provision of this section may be charged in the alternative in a single affidavit.
(D) No person shall operate a motor vehicle, trackless trolley, or streetcar upon a street or highway as follows:
(1) At a speed exceeding fifty-five miles per hour, except upon a freeway as provided in division (B)(13) of this section;
(2) At a speed exceeding sixty-five miles per hour upon a freeway as provided in division (B)(13) of this section except as otherwise provided in division (D)(3) of this section;
(3) If a motor vehicle weighing in excess of eight thousand pounds empty weight or a noncommercial bus as prescribed in division (B)(11) of this section, at a speed exceeding fifty-five miles per hour upon a freeway as provided in that division;
(4) At a speed exceeding the posted speed limit upon a freeway for which the director has determined and declared a speed limit of not more than sixty-five miles per hour pursuant to division (L)(2) or (M) of this section;
(5) At a speed exceeding sixty-five miles per hour upon a freeway for which such a speed limit has been established through the operation of division (L)(3) of this section;
(6) At a speed exceeding the posted speed limit upon a freeway for which the director has determined and declared a speed limit pursuant to division (I)(2) of this section.
(E) In every charge of violation of this section the affidavit and warrant shall specify the time, place, and speed at which the defendant is alleged to have driven, and in charges made in reliance upon division (C) of this section also the speed which division (B)(1)(a), (2), (3), (4), (6), (7), or (8) of, or a limit declared pursuant to, this section declares is prima-facie lawful at the time and place of such alleged violation, except that in affidavits where a person is alleged to have driven at a greater speed than will permit the person to bring the vehicle to a stop within the assured clear distance ahead the affidavit and warrant need not specify the speed at which the defendant is alleged to have driven.
(P) (1) A violation of any provision of this section is one of the following:
(a) Except as otherwise provided in divisions (P)(1)(b), (1)(c), (2), and (3) of this section, a minor misdemeanor;
(b) If, within one year of the offense, the offender previously has been convicted of or pleaded guilty to two violations of any provision of this section or of any provision of a municipal ordinance that is substantially similar to any provision of this section, a misdemeanor of the fourth degree;
(c) If, within one year of the offense, the offender previously has been convicted of or pleaded guilty to three or more violations of any provision of this section or of any provision of a municipal ordinance that is substantially similar to any provision of this section, a misdemeanor of the third degree.
(2) If the offender has not previously been convicted of or pleaded guilty to a violation of any provision of this section or of any provision of a municipal ordinance that is substantially similar to this section and operated a motor vehicle faster than thirty-five miles an hour in a business district of a municipal corporation, faster than fifty miles an hour in other portions of a municipal corporation, or faster than thirty-five miles an hour in a school zone during recess or while children are going to or leaving school during the school's opening or closing hours, a misdemeanor of the fourth degree.
(3) Notwithstanding division (P)(1) of this section, if the offender operated a motor vehicle in a construction zone where a sign was then posted in accordance with section 4511.98 of the Revised Code, the court, in addition to all other penalties provided by law, shall impose upon the offender a fine of two times the usual amount imposed for the violation. No court shall impose a fine of two times the usual amount imposed for the violation upon an offender if the offender alleges, in an affidavit filed with the court prior to the offender's sentencing, that the offender is indigent and is unable to pay the fine imposed pursuant to this division and if the court determines that the offender is an indigent person and unable to pay the fine.