Baltimore County police are crediting the county's alarm-reduction ordinance for a sharp drop in the number of false alarms last year.
The department released statistics this week showing that the number of calls for alarms dropped 21 percent last year compared with the year before.
Authorities estimate that 98 percent of alarm calls are false.
The County Council established fines in 1998 for businesses that experience more than three false alarms in a year. The fines range from $50 to $1,000. The law was applied to commercial sites in 1998 and to homes in 1999.
"This is not to raise money, this is meant to change behavior," said Bill Toohey, a police spokesman. "The less revenue this generates, the better off we are."
When a burglar alarm goes off by mistake, it takes about 16 minutes for an officer to investigate, police said.
Last year's drop in alarm calls included a 24 percent decline in residential alarms and a 16 percent decline in commercial alarms.
Alarm calls in the county peaked in 1998, when police responded to 86,499. That number dropped to 68,343 in 1999. Last year, police responded to 53,877.