HARRISBURG - State Rep. John T. Galloway was arrested early Tuesday for driving under the influence just blocks from the Capitol. By late afternoon, he was apologizing for "a very serious mistake."

The lower Bucks County Democrat was pulled over shortly before 2 a.m. after a police officer spotted him driving erratically, running a stop sign, and not using his turn signal, according to Capt. Annette Oates of the Harrisburg police.

Galloway, 50, who was alone and using his personal car, told the officer he was coming from the Capitol complex. Detecting alcohol on Galloway's breath as well as slurred speech, bloodshot eyes, and an inability to stand without assistance, the officer gave Galloway a field sobriety test.

The legislator failed the test, Oates said. He later was asked to take a Breathalyzer test, but he refused, according to police.

The officer placed Galloway under arrest. He was to be charged by summons with driving under the influence, failing to use his turn signal, and failing to stop at a stop sign, police said.

Galloway, a Levittown native who is in his third two-year term representing the 140th District, issued this statement late Tuesday afternoon:

"Last night, I made a very serious mistake. I drove after drinking alcohol. I was pulled over in front of my apartment in Harrisburg. I cooperated fully with the police officer. It is my understanding that I will be charged with driving under the influence of alcohol."

"There is no excuse for drinking and driving," he continued. "I apologize to my family, friends, colleagues, and the people I represent. Most importantly, I am thankful that no one was injured as a result."

Oates said she did not know how long Galloway was kept in custody Tuesday morning, but said police protocol was to hold a suspected drunken driver until he or she is sober. Galloway was placed on legislative leave Tuesday at the request of the House Democratic caucus.

Refusing a Breathalyzer test leads to an automatic one-year suspension of driving privileges. A DUI conviction can result in a brief jail sentence, but defendants can avoid that if they complete a probation program for first offenders.

Galloway is the third area legislator in recent weeks to face criminal charges related to driving.

In early May, State Rep. Cherelle L. Parker (D., Phila.) was arrested and charged with driving while drunk in the city's Germantown section.

A Philadelphia police officer pulled Parker over after observing her allegedly driving the wrong way on a one-way street.

Also last month, State Sen. Bob Mensch (R., Montgomery) was convicted of disorderly conduct. State police said another motorist reported that Mensch displayed a handgun while both drivers were locked in a high-speed encounter in early March on I-78 in Berks County.

Mensch, who has a concealed-weapons permit, is appealing his conviction. He has told the Easton Express-Times that he never brandished a gun - instead holding a cellphone - and wants his conviction overturned.

Contact staff writer Angela Couloumbis at 717-787-5934 or acouloumbis@phillynews.com.