It’s good to be an incumbent running for re-election when crime is down.

Montgomery’s numbers are a sweet spot in County Executive Isiah Leggett’s two-term record, and he used them to good advantage in Thursday evening’s forum at the Long Branch Community Center with his 2014 challengers, Democrats Doug Duncan and county council member Phil Andrews and Republican James Shalleck.

Total crime in the county is down 9 percent from 2012, with serious offenses--murder, rape, robbery, aggravated assault, burglary, larceny, and auto theft--down by a third over the last seven years. That’s way ahead of the nationwide drop in crime.

“That didn’t happen by accident,” Leggett told a small gathering at the event, sponsored by Safe Silver Spring, a community anti-crime group.

He attributed the drop to his funding of the police department, which has had 28 percent spending boost on his watch. Full-time sworn and civilian posts are up by more than 100. His proposed 2015 operating budget would add an additional 23 officers and two forensic scientists.

As social scientists like to say, however, correlation is not causation. While Leggett’s policies may have contributed to the county’s downward trend, he’s also surfing waves of complex demographic, economic and cultural forces that drive crime rates.

Still, the numbers left Leggett’s opponents with not a whole lot to offer beyond support for initiatives that he already has in place, including after-school programs and the Family Justice Center for domestic violence victims.

Duncan and Shalleck talked about adding more police presence to schools. Andrews took a poke at Leggett for his unsuccessful 2011 attempt to gain council approval for a teen curfew (11 p.m. curfew on weeknights, midnight on weekends), a measure Andrews opposed.

“I asked the hard questions about that,” he said.

Leggett didn’t respond.

While his challengers emphasized tougher enforcement on issues like truancy and domestic violence, Leggett, who has a background in the civil rights movement and as a law professor, talked about holistic strategies to stabilize families and engage communities.

He was alone among the four in making the point that federal immigration policy impedes the ability of police to build bridges in neighborhoods. Latino residents are often afraid that their immigration status will be used against them if they come forward with information about crime.

While crime is down overall, the picture is not as positive in Long Branch and other eastern Montgomery neighborhoods along the Prince George’s County line. Thursday night’s audience, dominated by middle-aged and senior residents, peppered the candidates with complaints about drugs, noise and lax parking enforcement. They said police often tell them that officers have higher priority calls to pursue.

The candidates were sympathetic, but couldn’t do much more than urge them to keep complaining to code enforcement officials and the police. Shalleck said the loudest voices are more likely to get heard.

“Call your councilman, the county executive, the police,” said Shalleck. “The people who complain, it drives ‘em crazy.”