The attorneys for both the Plaintiff and the Defendant typically exchange written discovery soon after the Answer is filed. There are some standard questions which must be answered by both sides. Also, each party gets to send specific Interrogatories (or questions) to the other side. Additionally, each side is allowed to request documents which might be relevant to the accident or the injuries.
On a truck accident case, for example, I request documents from the defendant trucking company relating to the federally required trucking logs to see how long the driver had been on the road at the time of the accident. I also request the GPS and maintenance records relating to the truck and the driver's employment file. This is just the tip of the iceberg of documents I request in a major truck accident case.
Each side has 30 days to respond to the other side's written discovery. During that 30-day period, the parties will meet with their respective attorneys, provide necessary information and documents and the attorneys will compile the final answers.
After written discovery has been exchanged, each side will typically evaluate what the other side has produced and determine whether any additional information is necessary. Many times the written discovery answers will prompt the need to request additional information from the other side or information from outside sources who are not involved in the lawsuit. For example, if I am suing a truck driver, I might subpoena his driving records in the state where he has a driver's license. I might subpoena his employment records from any of his previous employers to see why he no longer works there. These files can sometimes be a treasure trove of information on a truck driver's past history.
Typically, in a personal injury case, the Plaintiff will be required to disclose all medical providers he or she has seen after the accident and all his or her medical providers seen for any reason in the 10 years prior to the accident. Once the Defendant's attorney receives this information, he or she will obtain the medical records from both the pre accident and post-accident medical providers (the attorney will do this even if he or she has copies of the medical records which were previously provided by the Plaintiff's lawyer).