
The SWAT team is almost never needed. Use them too much and your popularity dwindles. Barricading roads is a bad idea unless you're aiming to get the boot. If you're willing to wait for a rookie to polish off his doughnut, it will make arrests easier. On expert level, use pedestrians as human shields.
As soon as the game begins get all officers into their cars and into strategic locations around the city. After a few games you'll get to know which are the key locations. Renko, Hill, Hunter, Coffey and Belker are all fast on their feet and can cover considerable territory. Bunt, Bates, Goldblume, and Washington are really slow, so keep them in known trouble spots. These are only examples of start locations so feel free to experiment:
Later on in this game, hunt down second-time offenders. This requires minimal effort and is guaranteed to put your efficiency rating up in the nineties. There's a rash of murders early on in the game which have to be solved quickly. Assign one of the five last officers to a case. Get him to the scene of the crime and keep him on screen. Get him out of his car and walk him around the block. If he's reached... <The rest of this sentence has gotten lost somewhere along the line>. Don't forget that all drug, armed robbery, and murder cases require the officer to stand up in court and identify the accused, so get a good look at them before you take them back to the station house.