Let's start at the beginning.
What is a Deposition?
A deposition is a question and answer session where a witness in a case is questioned under oath about their personal knowledge regarding the facts of a particular case.
How Are Depositions Usally Taken?
In most cases, the depositions are transcribed by a court stenographer, who later reduces the question and answer session to a written transcript, which is in turn later turned over to the witness for his or her signature attesting that their answers were true.
Although very unusual, there are circumstances where a party to a case may wish to go to the extra expense of also having the entire deposition videotaped. To that end, New York Civil Practice Law and Rule 3113(b) provides that deposition "testimony shall be recorded by stenographic or other means, subject to such rules as may be adopted by the appellate division in the department where the action is pending." In addition, the Uniform Rules for Trial Cts [22 NYCRR] §202.15 permits the taking of a deposition "by means of simultaneous audio and visual electronic recording."
When Videotaping a Deposition Might Be Warranted
The primary instances where parties have gone to the trouble and expense of having a deposition videotaped is where you expect (or have reason to expect) that a critical witness that is currently available may be unavailable at the time of trial. The reasons for this could be one of several, such as where the witness is currently in your jurisdiction, but is not expected to be so later, or where the witness is suffering from a grave medical condition and might not survive until trial.
The advantages to videotaping the deposition under these circumstances should be fairly obvious: it allows the testimony and mannerisms of the witness in response to the question to come alive, rather than being limited to a dry, black-and-white transcript. See, e.g., Fajardo v. St Joseph's Med. Cntr., 192 Misc.2d 369 [Sup.Ct. Bronx Cnty. 2002].