Are the video files of recorded depositions for lawsuits by both the plaintiff and defendant(s) public record? and can I make a FOIA request to obtain these video files?
The question of whether they are a public record or not is more subtle and complex than it appears with a poorly developed case law (e.g. it goes to the question of whether a third party is allowed to be present at a deposition), but fortunately, isn't necessary to answer the question in this case.
You cannot make a FOIA request to obtain these video files because they are not in the custody, control or possession of a governmental body, so they are not subject to a FOIA request. Video deposition files are created by the court reporter/videographer (a private business) and are shared with counsel for parties after the parties pay the court reporter/videographer's fees for their services. Unless they are submitted at trial in evidence, they never become a part of a court file.
It isn't inconceivable that they could be obtained by subpoena from counsel or the court reporter/videographer in a proper proceeding, but that proceeding would not be a FOIA request.