(CNN) -- Motorists in Ohio, beware: Speeding is in the eye of the beholder, especially when police are the ones guesstimating.

The Ohio Supreme Court has ruled a trained officer's "visual estimation" of a vehicle going over the posted speed limit is enough to convict a motorist.

Local law enforcement agencies say the ruling in their favor does not mean they will stop using radar guns, while the guilty driver's lawyer says the decision "stinks." That man was cited for going nearly 20 mph over the posted limit.

The state high court by a 5-1 vote said a trained officer's guess was, by itself, enough to allow a ticket for speeding.

"A police officer's unaided visual estimation of a vehicle's speed is sufficient evidence to support a conviction for speeding in violation of [state law] without independent verification of the vehicle's speed if the officer is trained, is certified by the Ohio Peace Officer Training Academy or a similar organization that develops and implements training programs to meet the needs of the communities they serve," wrote the state justices. The said a radar gun was ''not necessary to support a conviction for speeding.''

The case involved Mark Jenney, who was traveling along Route 21 near Akron two years ago in his black SUV.

Officer Christopher Santimarino of the Copley, Ohio, Police Department was in his parked patrol car and saw Jenney drive by and determined the motorist was speeding. He was cited for going 79 in a 60 mph zone. At trial, the officer testified the radar unit he was using at the time clocked the vehicle at 82 mph but that reading was tossed by the judge after Santimarino could not producer a copy of his radar-training certificate when requested.

Santimarino -- who said he had performed "hundreds" of past visual estimations -- claimed he cited Jenney for only 79 mph "to give him a break on the personal appearance in court." The judge in upholding the conviction concluded the officer's "strongest" testimony was his visual estimation, but amended the citation to say Jenney was only going 70 mph.

For his part, Jenney said he was not speeding and that the real culprit was a tractor-trailer that was passing his SUV at the time.

Copley police defended their officer's actions.

"Officers can rely on their unaided visual estimation of a vehicle's speed, but the intent is not to allow officers to routinely issue tickets based solely upon unaided visual observations," said Chief Mike Mier.

John Kim, the attorney representing Jenney, said the decision "stinks" and expressed disappointment the state court did not rule on his main point -- when radar readings are disqualified, visual estimations should also be dismissed.

''I'm really surprised,'' Kim said. ''I never expected the ruling to come out this way.''

Jenney paid the $177 fine, and his lawyer says he has no further plans to appeal.

The case is City of Barberton v. Jenney (2010-Ohio-2420).