It depends on several factors of your situation. What is your goal? Specifically, did you receive a ticket that you are wanting to fight? Are you being sued? Are you trying to recover from your own or the other person's insurance company?
In any event, you should inform your insurance company as soon as possible if you haven't already. Also, you should inform them of your version of the events as soon as possible, and make sure they take it down. If it is an insurance recovery thing (or a personal injury suit) your insurance company may be obligated to defend you or pay for a third party lawyer to defend you against another party. If you are battling with your own insurance company, and they are being difficult, you might want to consult with an attorney to secure your rights.
If you are facing the ticket you feel is unjust, you can challenge it. In many cases, police officers are too busy to show up to traffic court, and you will win by default. HOWEVER, if you challenge it and the officer does show up, it will be difficult for you to prevail (but not impossible). Traffic court is a fast-moving, stressful process, and the judge hears "the cop is wrong" all day long. You may get short shrift and be assessed court costs. You might win if your testimony (that you were in the other lane) is believable and not controverted by the police officer's testimony, and if it demonstrates you were not "following too closely." You should consider very carefully whether it is worth it for you to risk the additional fees. For challenging a traffic ticket, you probably do not need an attorney. It may improve your chances of succeeding, but since your argument is purely he said/she said facts a lawyer may not be able to add much. It is probably not worth the additional cost of an attorney.
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