I decided to make guide for cops, who gonna be them, or who want to catch more warrants, take more skills and improve stats. First of all, i must to say that my english is bad, don't judge.
Catching suspects is hard work, which consists of shoot skills and driving skills. Driving skills means, your keyboard works correctly and lag-pitting suspects. More information about lag-pit and other police stuff here: http://forums.crazybobs.net/viewtopic.php?f=11&t=2508
But i want to tell you, driving skills is not only that, it's stealth and intuition on next suspect's actions. That's all you need while chasing warrant. This included in police maneuvering, that can help you to takedown them.
There exists 16 maneuvers, that can be useful in chase:
1. Return
2. Lag-pit + police return
3. Hit
4. Hit at start of moving
5. Hit at crash
6. Zigzag
7. Head-on coliision
8. "Clamp"
9. Lag-pit at crash
10. Artful overtake
11. Lag-pit + roadblock
12. Clamping to the roadside
13. Roadblocking
14. Interception
15. Team chasing
16. Close encounter
1. Returning
This is good maneuver against suspects which can move after you and you see him in back. Also you can just being stop at roadside. If you see running suspect in back, turn the car to the side, so it was unexpected for him. You can even turn on 360 greeds to make him "clapped", also use your uzi.


Althought suspect can be smart and drive to other way you turned. Well, if you can anticipate it: start turn and stop the car so this was unexpected for him. Keep in mind, your car will be hitted. But still you stopped a suspect, and have a bit time to destroy his vehicle.
There's one more returning maneuver. This means you must to overtake a suspect and return the car on 360 degress to make him lag-pitted to roadside. After you did it, just use weapons to damage his car.


2. Lag-pit + police return
When you intercept the suspect he can drive on you. If want to stop the suspect effectively, make police return right on his drive way.


This maneuver will flipback suspect's car and you have some time to destroy it fast.

In other way: make police return and close the path by your car. Your car can be hitted, but still you stopped the suspect. Use weapons in this moment.
3. Hit
This maneuver can be effective if suspect stopped to use ACME Instafix or his car just being stopped.
When you drive to the suspect and see he's stopped, hit the car in side or hood to make him threw/flipped. If suspect tried to use instafix, and you succesfully completed the maneuver, by not giving this to him, his car will explode and he will be jailed


If after this maneuver your and suspect's car turned to the roadside, fast use uzi and block wayouts.

4. Hit at start of moving
This something like lagpit. Suspect's car was fixed and he ready to drive. Just see where to its car directed and block the way. If car starts to move, try to lagpit it.

5. Hit at crash
Sometimes chase is fun. There action, explosions, ups and downs

[youtube][/youtube]
6. Zigzag
Sometimes on big speeds difficult to chase someone, especially if you in back. But if you got a luck to overtake the suspect you must try to lagpit him. Sometimes this succesfully, but not for smart players. They can anticipate your actions and avoid lagpits, or you can be lagpitted by them. Try to behave like a mad driver, go left-right, left-right... Differently its called zigzag. You must to watch carefully, to not be crashed or will long catch the suspect.

Also watch your back, to not drive away from your lagpitted victim too far xd. If this happened, return the car (police return) and drive on suspect to hit him or block wayouts. Also use weapons, suspect must be taken down.

7. Head-on collision
It seems like car suicide xd, but if want to takedown the suspect by this method, his sportcar will be damaged more than you (considering you use basic copcar). If see suspect drives on you, hold the drive path and try to do same. Sometimes you must to confuse him, to make him crashed on you, but this is your work.

His car will be flipbacked and too damaged. Use everything to finish this.

8. "Clamp"
Let's imagine suspect crashed, stucked or you made good lagpit. This is important moment to block him and maximally damage his vehicle. Vehicle can be flipped or be stay on 2 wheels. General in this maneuver is immobilization suspect's vehicle. Either he give up nor try hard. In this moment you also can use weapons.


9. Lag-pit at crash
Suspect can use stunt locations to troll you. Also he can just get down from the hills, car can be on 2 wheels with failed stunt. If you drive fast, you can lagpit him. Watch his driveway to complete maneuver succesfully. Example in video below:
[youtube][/youtube]
From this lagpit the suspect's car will be more damaged as it can flipbacked to buildings or passing driver players. Will more fun if this happen few times

10. Artful overtake
Here is. You are alone, 1v1 with suspect. You trying to lagpit him but he already knows what you wanna do. Anytime you can be lagpitted and chase will over. Behave unpredictably while chasing suspect, he knows you want just to lagpit him. Low the speed and drive after him, suspect will turn right-left and try to remove you, start do same to overtake and lag-pit him. While suspect turn his car by trying to lag-pit you, he slown down and gives chance to lag-pit him. Example in video below:
[youtube][/youtube]
11. Lag-pit + roadblocking
This is one of effectiviest method to lagpit the suspect. When you chasing, you must be agressive to the suspects. Drive aggressively but professionally!
No matter, from which side you gonna lagpit the suspect. Your task to lagpit him at side of the car, drive away a little bit further to the roadside by not slow down, and turn own car on 90 greeds to block suspect's drive path.

GTA physics is unpredictable, probably you again lagpit the suspect when will turn own car. But that depends from player's driving style. If he will be "clamped", use uzi in this moment.
Otherwise, suspect will be knockbacked to other roadside from your turning. Then, after you turned car on 90 degrees, drive fast to catch block the wayout. This depends from your car speed and reaction.

12. Clamping to the roadside
This is compulsion for stopping. Overtake him, drive in the other part of the road, and turn the car on 90 degrees to the roadside where suspect drives. Get a right moment to do this maneuver, you must look forward and in back to clamp the suspect to the roadside.

After this succesful lag-pit use weapons to end it.

13. Roadblocking
When you drive toward the suspect, or just wanted to pass but saw unexpectedly him you must to know something. Need to start turn for roadblock/lagpit from the other part of road. Like if you drive right, turn left the car on 90 degrees and stop fast. Drive left - turn right, and do same.


To make correct 90 degrees maneuver, control your drive, remember drift lessons. Keep fingers to the buttons of keyboard tightly, to do it. Maybe, you will get used to this.
If you drive toward the suspect with "helper", second cop unit. Stay at your part of the road, and turn your car on 90 degrees to make roadblock. Would be good, if second cop unit do same.


Suspect will be at a loss, anyway he can be lagpitted/flipbacked. If that's not happen, you should to run after him.
Differently, some one of cop units can make roadblock maneuver, second continues driving to lagpit the suspect. Otherwise, he can pass at roadside, this depends from his decision.

But if he taken a "wrong decision", his car will be lagpitted, flipbacked, use uzi in this time.

14. Interception
Useful maneuver, that helps to catch the suspect there, where to he drive. Interception is required knowledge of locations, San Andreas map, and of course driving skills. As a rule, failed interception will let the suspect to go away, and there many things that can afford i. If you are spotted a suspect in the radar, who run from cops follow the parallel street and navigate with it.

If the chase crossing with you, i can recommend to use a lagpit directed from corner as it can be more effective but you can use other methods like roadblocking, shotting from car window or whatever.

With knowing city and map locations, also stunt and secret driveways will increase chances to catch the suspect, depending how you will do it.

There's one more method: If you chasing a bank/casino/other robbers, try to intercept them at direction of point of money collecting. Navigate on map with chasing suspect to detect it.
NOTICE: Point of money collecting is random and differents for each cities, so by chooicing where to drive for interception you rely on own intuition.
Some of points are presented below.

15. Team chasing
Half of chases is ends after cops cross road intersection: cars can't share the road: someone lagpitted, someone crashed, players cop dm each other, the end. Solution consists in elementary algorithm of actions: every unit must to keep its lane and drive the path direction that not crossing with other's units. Example, like shown in picture below, Unit A must to have an advantage in the intersection as he will make a drift maneuver, meanwhile Unit B must to drive through sidewalk/corner if there's enough space. Of course, this is not comfortable direction for Unit A but there will no crash. In dependeing who is forward, someone should to keep distance.

Try to not cover your team unit in back, watch careful. If you've accidently got his lane, give him a freespace (especially for sportcars, and cop tanks who like to pop tires form being mad).

16. Close encounter
At chasing of suspect, many of obstacles. Avoid them, and don't be like this too! Main obstacles that is random civillians, bots and team cops - you must to try avoid crash with them for chasing the suspect and not let him go away.
When you joining the pursuit, don't cover driveways of chasing units - This is moments when pursuit ends. Best way is to turn on roadside and drive on it or stop until unit cars will drive away, after you can follow them.

Situation that can happen any time: someone crashed and try to get back to pursuit, someone joining the pursuit by covering driveway and you have obstacles to catch the suspects. Not all avoid this. Be careful at these moments as there many crashes happen.
Example, you heading after suspect, and crashed Unit B returning to back in pursuit, Unit C is joining the pursuit. If Unit B is returning, you can drive on path 1 to avoid crash with Unit C, that can cover the driveway.
If Unit B still not returning, but Unit C covering all road drive path 2.
If Unit C drive in path 2, you can drive right lane, and car will be a forward.

Situations can be different, and ammount of cops in the road too.
You will have special advantages if will do these maneuvers fast and chooice priority between them to takedown the suspects.
This more can improve your police skills and stats.
Important to watch the suspect, whom you want to takedown by using these maneuvers. This needed to anticipate his actions and complete maneuvers correctly.
Use basic copcars or modified sportcars, whatever you want. But best car is which good driveable.
This guide created on my experience.
Thanks Avt_0002 and ehsan_afzaL for help in making video.