Probably the biggest reason you need an attorney is to navigate the legal procedures involved in your legal matter. Whether your matter is a transaction or contract that must anticipate legal procedure or a litigation matter that must deal with legal procedure first hand, the only way to be confident that you will come out on top is to rely on the counsel of an attorney who is a specialist in legal procedure.
A close second to procedure is evidence. No matter if your immediate issue is transactional or litigation, underlying every step of your solution is the law of evidence. Non-legal professionals are notorious for failing to appreciate the requirements of the legal system when it comes to evidence. Handshakes and oral agreements make it difficult to prove what really happened or what was truly agreed to at any given time. The only way to be sure that your matter is resolved in a way that complies appropriately with the rules of evidence is to rely on the counsel of an attorney.
The Right Words
Words are powerful. While many people still complain about too many lawyers in government, more mischief has been caused by poorly worded statutes than by any lawyer in the legislature. Even among attorneys, horror stories abound in which a judicial order, a contract or a pleading failed to properly describe the matter causing many unintended consequences. No matter the issue you are facing, the counsel of an attorney can help you properly capture your true intent in the right language to get the result you truly desire.