The First Department explained the elements of the offense of tampering with physical evidence as follows:

…[A] person is guilty of the completed crime of tampering with physical evidence when, “[b]elieving that certain physical evidence is about to be produced or used in an official proceeding or a prospective official proceeding, and intending to prevent such production or use, he suppresses it by any act of concealment” (Penal Law 215.45[2]).

The offense of tampering does not require the actual suppression of physical evidence, but only that a defendant perform an act of concealment while intending to suppress the evidence…. Regardless of whether the defendant is successful in suppressing the evidence, once an act of concealment is completed with the requisite mens rea, the offense of tampering has been committed.  People v Eaglesgrave, 2013 NY Slip Op 05001, 1st Dept 7-2-13