Firstly, not enough people who are caught fight it in court, they simply accept it, get the points and pay the fine.   If more than 10% fought the ticket I think the judicial system dealing with this would be overwhelmed and brought down on its knees.  If in doubt, fight it.  The worst thing that can happen is that you will be convicted of you original offence.  You can get a heftier fine and  more points in court, but unless you were doing silly speeds, its unlikely.

Make the systems life  HELL when fighting it.  Remember it is going to cost the system a huge amount of money to prosecute you, in the officer's time, court's time, prosecutor's time etc.  The best thing you can do is make it worse for them.  (Revenge is sweet)

Here are some steps you can take.

Just as a byline, I asked a normal officer what he think of Radar guns, and he hates them.  He said he thankfully has nothing to do with them.   Bear in mind then, the officer may not be in the best of moods.

What to do at the scene

It is critical that you start contesting your ticket at the scene of the alleged offence. It is also CRITICAL that you remain cool, calm and composed; keep you wits about you and do not get mad.  You must judge the officers temperament and situation (is it a nice bright day, and the officer will be lenient or is it pouring down and he wants to book you and go home) and decide the approach for yourself .   You are more likely to get let off by a normal officer (black hat, black uniform) than by a traffic officer (white hat, green overcoat).  Remember, its a traffic cop's job to catch you, the normal cop probably does not want the added paperwork (I know someone who was let off in town for doing 70mph because he said he thought he was still on the motorway).   If the officer asks you how fast you think you were going you can take one of three approaches:

1. You can deny it outright and tell him you weren't speeding, that you checked the speedometer.  DO NOT get into an argument, but do not admit guilt.  This is unlikely to prevent him from giving you a ticket, but you can tell judge at a trial that you were not speeding and you checked the speedometer, you can have the officer confirm that in your cross examination of him. This will serve to make your case stronger.
2. You can say that you are not sure, your mind was elsewhere. If he insists you were speeding, then sidestep by saying something like, "I can only assume I must have been otherwise you would not have stopped me".  DO NOT admit guilt,  this approach simply reiterates the officers accusation.  This is difficult to use as evidence in court on both sides.
3. Be honest and admit guilt.  If you are stopped by a traffic officer, then it is fair certainty you are going to get a ticket anyway so this is a stupid approach.  If it is a normal officer, you may get off for being honest. This approach relies on luck.  Forget fighting it in court if you admit guilt.

Normally, NEVER admit guilt, even if you do not intend fighting it, none of the I have a plane to catch, I'm late for work, my house is on fire, my wife's giving birth in the back. (Ok, you may get off for the latter 2 and may even get an escort). 

All speed pacing police cars have to have their speedo's measured and certified.  Only traffic police cars are done, and the speedo will have increments of 1 mph's.  If you are stopped by a non traffic officer, and told that he/she followed you and you were speeding, simply ask as a matter of course when his speedo was last calibrated.  It is likely he will let you go since normal police (beat) cars do not have certified speedo's, theirs is the same as mine and yours and can not be used as evidence.

NEVER surrender your license at the roadside, you will get a chance to take it to a police station.  Surrendering you license at the roadside is an admission of guilt.  Surrendering it at a police station later is just abiding by the law.

If you are given a ticket, study it carefully before leaving the scene. The officer will ask if you have questions about the ticket, and you will:

DO NOT get cocky at the scene, you have nothing against the police officer, he/she is only doing his/her job.  It is the system that you want to fight (legally I mean!).

If you were caught on a Radar gun.

Ask to have a look at the radar gun and check that the gun displays the speed that you were stopped for.  Remember, the police officer is not obliged to let you do this.  As a con, this is also going to make you less inconspicuous, so he may remember you well in court.

If possible, get the make, model and serial number of the radar gun.

Ask the officer to demonstrate that the radar gun is calibrated (he will probably not do this, if not assume it is not calibrated and use it as evidence).

Do not regard self diagnostics as accurate, Radar guns are calibrated with a pair of tuning forks, and only this external test may be considered accurate.  

If the officer refuses to demonstrate the calibration, ask him to prove that he has tuning forks in the car (he will probably not be too happy at this point, but he can not do anything, your requests are legitimate, although he is not obliged to do it).   If he doesn't, tell the judge because this means (at least in your eyes) that that the gun is not calibrated.

If you were caught on a  LIDAR gun.

Ask to have a look at the laser gun and check that the gun displays the speed that you were stopped for.

If possible, get the make, model and serial number of the laser unit.

Note the positioning of the unit in relation to the sun or any other bright red or white light. LIDAR uses infrared light., and does not work as well when aimed into infrared light sources like the sun or high beam headlights.

Ask when the unit was last calibrated.

Ask to see a demonstration of the calibration.  the same notes apply for the RADAR gun. These however, are not tuned by forks (I do not know how they are done).

YOU MUST MAKE NOTES AT THE SCENE.   The officer certainly will.  In court you may be asked if the notes were made while the events were still fresh in your mind.  If you want to use the notes, then the answer must be a yes. Note the following:

• The answers to any questions you asked the officer.
• Any items you noted above.
• Positions of OTHER CARS.  You may be able to claim that he metered someone else, but stopped you (particularly lorries, since radar is good at locking into a larger object)..
• The weather conditions.
• The time and date.
• Your direction of travel and the source and destination.
• The lane you were in and the name of the road, also the area.
• The officer's direction of travel and lane, or note if he was parked
• A brief physical description of the officer so you recognize him in court (PHOTO if possible)
• Take the officer's number, and the unit number on his car.

If you were caught on a Camera.

The police MUST send you a notice of intended prosecution within 14 days.  If they do not, the case is a non-starter. (Unless it took longer to trace you because you have a company/hire car)

Preparing for Trial

Examine the ticket a few times.  Look for mistakes on the ticket such as a wrong name, time, date, or location. if there are any,  you should tell them to the magistrate.

Gather evidence, you should write to the police and ask for at least the following items:

• Full copy of the Instruction manual for the RADAR/LIDAR device used. (You may get told that this is a breach of copyright, so, ask for the original and leave a deposit or something)
• Copy (both sides) of the calibration certificate.
• Details of the training (copy of certificate if there is one) given to the officer in the use of the PARTICULAR device.

I also recommend that you return to the scene and take pictures of the area, including any signs which indicate the law. Make sure that your pictures are clear.   DO NOT use a digital camera, to the best of my knowledge its not admissible.

If the Crown Requests an Adjournment

An Adjournment is a postponement of the original trial date. The prosecution  may ask for an adjournment because the officer cannot appear on the trial date which was set. If possible DO NOT agree to this, tell the judge that you had to book/take a day off work to appear or something (try not to lie :o).  This way, it may not be possible for the officer to appear or something, this can only serve to strengthen your case

Make note of any irregularities in the procedure in your statement to the judge. Irregularities include things such as the wrong ticket number printed on the  notice, a silly reason for requesting adjournment (such as a planned holiday, which the police should have known about before setting the  date), or receipt of the adjournment notice too close to the trial date.   It is possible that if you protest the adjournment, it will be denied.  In this case (no pun intended) the charges should be dropped since you can't have a case without the officers presence.

In Court

Check in with the prosecutor and usher and make sure you are on the case list, and that he knows you have appeared for trial. This is just to make your presence known, and hope that may offer a plea bargain at this point, which you could consider. He may not.

Look for the officer. If he doesn't appear, the charges should be dropped. This is where it is handy to reference the physical description you should have taken at the scene. If the officer does appear he may approach you and ask to talk to you before the trial. You don't have to, but it is polite to. Ask him to withdraw the charge, he won't likely do that but hey, you don't ask you don't get.  DO NOT indicate your strategy to him, or show him any notes or pictures. Keep this stuff in a manila envelope or briefcase so that it is out of view prior to the actual trial.

Cross Examining the Officer

This is your chance to put your notes and pictures to work. Ask the officer questions about the day to establish whether he really remembers the incident and you. If he doesn't seem to (this is where if you chose to be inconspicuous at the scene it helped), ask him directly whether he really remembers what happened that day. Destroying the officers credibility is an excellent way to get acquitted, you may like to take the opportunity first to remind him that he is under oath (ok, that may only work in the   American movies but it sounds good).

Ask about the radar or lidar equipment. If the officer refused to demonstrate the calibration, ask why and demand to know if the unit was truly calibrated. Each situation is different, but you should be able to use your notes to develop a strategy which insinuates that the equipment or officer used to clock your speed was not accurate. If you achieve this you will be acquitted.

Ask the officer about the laws in the catchment area. This includes turn controls, signalling devices, speed limits, and so on. If he doesn't get it right, use your pictures of the area to prove that he is wrong. Showing that the officer does not understand the laws in effect in the area is another good way to reduce his credibility as a witness against you.

You can try to go for the attack that the clocking may have been racially motivated. THIS IS VERY DANGEROUS and proceed with caution, remember he probably did not see your face when he clocked you.  If all goes well, you may make the officer lose his cool and throw a wobbly, this will drop his credibility.  Or you may end up with a charge of contempt.  Personally, I would leave this side of things unexplored, if it true however, seek legal counsel.

Courtesy and Appearance

Do not underestimate the impression of a shower, clean shave, haircut, and nice suit and tie at the trial, avoid jeans, t-shirt etc. You will look more innocent in this type of dress, and your chance of acquittal or fine reduction will be improved. You must also be courteous to the judge and officers of the court. If you make the judge mad, you will be convicted, so don't make him/her mad.