Most Baltimore police officers rely on city maps to help pinpoint crime spikes and deploy the troops to tamp down violence. But Baltimore Police Lt. David Engel has a different kind of map hanging on his office wall -- one of the world.
The map reflects the mission assigned to Engel, commander of the city intelligence unit, and his 36 detectives. Working closely with federal agents specializing in national security, the city's intelligence team tracks global flare-ups of terrorist activity, scans the Internet and pumps informants for tips about potential threats. Among them, the detectives speak more than a dozen languages, and some are experts on detecting fraudulent documents, an important skill because terrorists rely heavily on forgery.
Their work is part of a growing national trend that has seen local police agencies becoming more involved in domestic and international intelligence, a mission that before Sept. 11, 2001, was almost the sole domain of federal agencies, such as the FBI and CIA.
Police departments across the country have created intelligence units, or beefed up existing ones, because of concerns that federal agencies do not have the manpower to track down tens of thousands of potential tips and leads -- any one of which could prevent a terrorist attack. And to help bridge the gap between law enforcement agencies, local detectives have joined federal anti-terrorism teams helping to expand the FBI's Joint Terrorism Task Forces from 35 to 66 nationally since 2001.
"There's an emerging use of police and officers for intelligence gathering," said Ritchie Martinez, president of the International Association of Law Enforcement Intelligence Analysts, a group that is pushing for better training and stronger ethical codes for police intelligence officers. "The only way to properly evaluate our response to threats is to have people dedicated to working the information."
Hundreds of police departments have assigned an officer or two to work on federal terrorism task forces, according to federal officials and experts on the issue.
Other agencies have taken preparations a step further.
The Maryland State Police created a Homeland Security and Intelligence Bureau. The Maryland Transportation Authority Police -- which patrols many of the state's bridges and tunnels, as well as Baltimore-Washington International Airport and the port of Baltimore -- hired an intelligence chief to coordinate the flow of information, and contributed officers to federal task forces.
Elsewhere, the New York Police Department stationed detectives overseas and hired a former director of operations of the CIA to lead its intelligence bureau. And the Boston Police Department doubled its intelligence unit.
Boston Police Superintendent John Gallagher, the chief of the department's detectives, said his intelligence unit was playing a crucial role in preventing a terrorist attack because his officers on the beat might be the first to learn about a plot.
"We are the ones on the street," Gallagher said. "We're the closest to what is going on. We may see things that never come to the attention of the federal government. It's important for us to keep our eyes and ears open to any potential threat."
Though police have eagerly embraced intelligence units, some express concerns, especially in light of recent alleged police abuses.
In Denver, police kept thousands of files on people with no criminal record -- a practice uncovered in a lawsuit by a civil liberties group last year. In April, New York police stopped collecting information about the political beliefs of arrested protesters after being criticized for the practice.
Baltimore police were chastised several years ago for sending undercover intelligence officers into public meetings to monitor debates.
"This is not just the paranoid imaginings of fringe groups," said David Rocah, a lawyer for the American Civil Liberties Union in Maryland. "There is a well-documented and sad part of our history, which is why people are leery of these units because they don't operate in the open."
For the most part, police executives say such concerns are unwarranted, and their files usually contain information that is available in other public records.
In Baltimore, police say they follow federal guidelines on intelligence gathering. They routinely review and expunge files after five years if people are no longer considered threats, said Engel, head of the intelligence unit.
Before Sept. 11, 2001, Baltimore -- like most police departments -- had a small intelligence unit of five officers who gathered information about street gangs, drug dealers and crime trends.
Some intelligence officers still do those jobs, but the unit has expanded and changed its focus to preventing terrorism.
In the weeks after the terrorist attacks, detectives assessed the vulnerability of the city's critical buildings, companies and institutions, and created a computer program that tells commanders what to do when threat levels are raised.
They also oversee security at major events, especially those that might be targets of terrorists.
When the Jewish Community Center Maccabi Games were held in the Baltimore area last year, Engel's officers worked closely with federal agents to glean clues about threats. The unit closed off streets around First Mariner Arena and flooded the area with uniformed officers and undercover detectives.
The unit's detectives, police say, work closely with federal agents on several task forces -- including the FBI's Joint Terrorism Task Force.
Those detectives, and several others in the unit, have federal security clearances, making it easier to trade information with federal agents.
"It's hard to ignore people you are sitting down with over coffee at a meeting next week," said Mayor Martin O'Malley, a strong backer of Baltimore's intelligence unit.
To help the detectives and top commanders filter information, police officials trained eight officers as intelligence analysts. They scan the Internet for overnight news while rooting through terrorism-related Web sites.
One recent morning, analysts briefed Engel about an overnight bombing of a hotel in Indonesia before he dialed into a conference call with other local police officials and Gary Bald, special agent in charge of the Baltimore FBI field office.
The FBI conducts the conference call once a week. On this morning, Bald took the local officers through a detailed list of suspicious activities in Maryland and the world.
After he finished his 15-minute briefing, police added tips about potential terrorist activity in their jurisdictions.
"When everybody communicates, intelligence sharing is much better," Engel said. "Local law enforcement interacts with hundreds of thousands of people across the country every day. Who knows what might have prevented a terrorist attack?"