BOSTON — Three Massachusetts officials said Sunday they will try to close what they call a loophole in state drunken driving law.

The Supreme Judicial Court ruled Thursday that motorists who admit there’s enough evidence for drunken driving conviction but aren’t technically convicted are not subject to certain increased penalties.

State Attorney General Martha Coakley, Democratic state Senator Katherine Clark of Melrose and House Judiciary Chairman Eugene L. O’Flaherty said they have proposed to amend the definition of a conviction to include those who admit to sufficient facts for a finding of guilty.

Their proposal also would consider as a first offense, for purposes of refusing a breath test, situations in which an individual has been referred to an alcohol or substance abuse treatment program as a result of a previous prosecution for operating while under the influence.

“We must respond quickly to close this loophole and ensure that repeat drunk drivers are taken off the roads for significant periods of time,” Coakley said.

Clark called the proposal a common-sense solution to maintain strong penalties against repeat drunk drivers.

The Supreme Judicial Court said the state Legislature didn’t change the legal definition of what constitutes a “conviction” when it passed Melanie’s Law in 2005. The definition includes people who plead guilty or no contest or those who are found guilty.

It doesn’t include people who “admit to sufficient facts,” which allows them to admit there is enough evidence for a conviction but permits a judge to eventually dismiss the charges after a probationary period.

The court ruled in the case of Paul Souza, who was first arrested on a drunken driving charge in 1997. Souza admitted to sufficient facts and his case was continued without a finding until he successfully completed a period of probation. After that, the charge was dismissed from his record.

Souza was arrested again in January 2010. He refused to take a breath test, and the Registry of Motor Vehicles suspended his license for three years, citing his earlier case. Under the law, his license would have been suspended for six months as a first-time offender.

Souza appealed. In its ruling, the SJC said Souza’s first case doesn’t fit the definition of “convicted” under Melanie’s Law, named after 13-year-old Melanie Powell of Marshfield, who was killed by a repeat drunken driver as she crossed a street in 2003