COLUMBUS, OHIO — Country singer Willie Nelson called Ohio’s 24-year-old law declaring the “pit bull” to be a “vicious” dog by virtue of its existence an “archaic breed discriminatory law.”

In an email to a Senate committee, Mr. Nelson, an ambassador for the Best Friends Animal Society, urged passage of House Bill 14. The bill would do away with the breed-specific language and make other changes to dog enforcement law.

“Ohio is the only state that discriminates against dogs who share a cluster of physical characteristics by classifying this group as ‘vicious’ without any regard to individual dog behavior,” the email reads. “These dogs are considered ‘vicious’ at birth, even though there are countless dogs of unknown heritage who are deemed ‘pit bulls’ who are wonderful family pets.

“In addition to being beloved pets, many ‘pit bulls’ are show dogs, search and rescue dogs, and service dogs,” Mr. Nelson wrote.

“The current law infringes on responsible dog owners’ rights to own any dog they choose, no matter what the dog’s appearance. Dogs, like people, are individuals and should each be judged on his/her own merits.”

The bill, sponsored by Rep. Barbara Sears (R., Monclova Township), passed the House 69-29 last spring. The Senate Judiciary Committee began its consideration of the measure Wednesday. Opposition has come primarily from lawmakers from urban areas where “pit bulls” have become a dog of choice for dog-fighting and to guard drug houses.

Current law defines a “vicious dog” as one that, without provocation, has killed or seriously injured a person, has killed another dog, or is of the general breed known as “pit bull.” House Bill 14 would replace that language with revised definitions of “vicious” and “dangerous” dogs and create a new classification of “nuisance” dog. None would include any breed-specific language.

“Recently, Toledo, the largest city in [Lucas County], had an extremely restrictive dog ordinance that is focused on pit bulls,” Ms. Sears told the Senate Judiciary Committee. “Toledo also has the highest dog license fees in the state and spent a large amount each year euthanizing innocent dogs that resemble pit bulls.

“Despite Toledo’s extremely restrictive ordinance that focuses on pit bulls, the number of dog bites actually rose in 2008,” she said. “Toledo’s ordinance did not address the irresponsible owners. It killed dogs.”

Toledo has since eliminated its breed-specific law. House Bill 14 would not overwrite local ordinances enacted in home-rule communities.

The state issue has attracted attention from across the nation as well.

More than 11,000 people have signed an online petition at Change.org calling on Ohio senators to remove “pit bull” from the state’s definition of vicious dogs.

Jean Keating, president of the Ohio Coalition of Dog Advocates, is leading the campaign, which has gained the support of actor Ian Somerhalder of television shows Lost and The Vampire Diaries.

In Ohio, this marks the second time that the House has passed a bill to eliminate Ohio’s distinction as the only state with a breed-specific law. Such a measure died in the Senate last session, but Ms. Sears said she’s confident that additions to the bill providing additional tools and fees to dog wardens will make the difference this time.

Under the bill, the most severe classification of a “vicious” dog would be one that, without provocation, has killed or seriously injured a person. A “dangerous” dog would be one that has killed another dog or been a three-time offender as a “nuisance” dog.

These two most serious classifications would trigger registration, liability insurance, signage, housing, microchip, and other requirements.

A “nuisance” dog would be one that while, off its owner’s property, menacingly chased, approached, or attempted to bite a person. The first offense would start a record with the dog warden. Critics have complained that the bill would essentially allow the dog a free first bite before restrictions are imposed on owners.