"Recognisances of witnesses" is discussed in an 1829 book on New York law.
The Revised Statutes of the State of New-York: Passed During the Years One Thousand Eight Hundred and Twenty-seven, and One Thousand Eight Hundred and Twenty-eight : to which are Added, Certain Former Acts which Have Not Been Revised, 3 vols. (Albany: Packard and Van Benthuysen, 1829), 2:709
If it shall appear that an offence has been committed, and that there is probable cause to believe the prisoner to be guilty thereof, the magistrate shall being by recognizance the prosecutor, and all the material witnesses against such prisoner, to appear and testify at the next court having cognizance of the offence, and in which the prisoner may be indicted.