Ideally, SWAT officers don't see themselves as paramilitary soldiers, but as peace officers. This might seem to conflict with their aggressive and often violent tactics, but the optimal outcome of any SWAT team call-out is one in which no one is needlessly killed or injured. That includes hostages, innocent bystanders, officers and even the criminals themselves. SWAT tactics are meant to intimidate and confuse -- using deadly force is a last resort.
A typical SWAT call-out starts with the on-duty team members out on patrol, training or doing other police work. They may hear of an incident over their police radio that sounds like it could require SWAT. At this point, they have been given no formal command to assemble as a team, but they may begin preparing their gear and heading to police headquarters if they aren't in the middle of something that can't wait. The procedure for officially activating the SWAT team varies from one department to another, but generally a high-ranking police official will make the call. If more team members are needed, off-duty SWAT agents will be paged.
It may take an hour or more for the team to assemble. During this time, regular patrol officers will have secured the perimeter of the scene and kept it under surveillance. Once the SWAT team arrives at police headquarters, they will be briefed on the situation before loading into their SWAT vehicle. This vehicle transports the team and their gear, and in many cases it is also equipped to serve as a mobile command headquarters. Whether they use a vehicle or a nearby house or office, the team sets up their command post close to the scene of the incident, but in a safe place.
At the command post, team leaders begin assimilating information. Background checks on the suspect, the layout of the area, known weapons involved, the number and disposition of hostages, potential motives -- any information could be useful. At this point, negotiators get in contact with the suspect (if possible) and try to get additional information. (For more information on hostage negotiations, read How Hostage Negotiations Work). If the SWAT team is missing some crucial information, such as the specific location of the suspect and hostages in a barricaded house, they will send team members to gather it using surveillance equipment. These recon units usually operate as two-person teams, and they are experts at stealth.
One thing SWAT teams have learned over the years is that crazed gunmen don't always wait around for SWAT to execute a carefully-conceived plan. The suspect could start shooting at officers, killing hostages or make an escape attempt. For this reason, SWAT teams develop a few "quick and dirty" contingency plans as soon as they arrive on the scene.
Given enough time, the team will formulate a more extensive plan based on all the intel they have gathered. They will determine if there will be separate teams, where they will enter, the timing of the entry, what ordinance will be used and other details. There may be preliminary steps, such as drilling a small hole in a wall and using a pinhole camera to keep an eye on the suspect, or using a distraction to draw the suspect toward a certain location. If the SWAT team is going to serve a high-risk arrest warrant, they can spend more time planning.
In the next section, we'll examine how a SWAT team typically conducts a raid.