While city officials routinely face heavy scrutiny and questions about the reliability of data, neighboring jurisdictions flaunt even greater gains in the fight against crime: Anne Arundel's crime rate is 47 percent lower than in 1975, while Howard County's is 54 percent lower.
Many criminologists say homicides might be the most reliable way to gauge broad crime changes, as those figures are the least likely to be manipulated. Indeed, the state's murder rate of 7.4 killings per 100,000 also reached its lowest level on record. LaFree said that would support the contention that the declines are real.
The state's largest jurisdictions have been boasting some of the biggest drops. Baltimore County experienced its lowest violent crime rate last year since 1976, and its 20 homicides were the lowest on record. Prince George's County saw its lowest violent crime rate since 1978.
Meanwhile, some smaller counties are seeing increases. Allegany County experienced a 10.7 percent increase in total crime last year and its highest crime rate ever. Its violent crime rate was more than double that of 1975.
Cecil County, which has seen crime increases in recent years, reversed the trend last year with a 9.8 percent reduction in violent crime and a 6.5 percent drop in property crime.
Maryland had the ninth-highest rate of violent crimes in 2009 with 590 per 100,000 people, according to the FBI's Uniform Crime Reporting program. That compared with Virginia's rate of 226 violent crimes per 100,000 people and Pennsylvania's rate of 380. Delaware had the fourth-highest violent crime rate at 636 per 100,000 people.
Zimring said it's impossible to predict where crime trends are headed.
"You cannot predict anything that you can't explain," he said.