NEW YORK -- Defense lawyers for ex-top Cuomo administration aide Joseph Percoco want the attorney for key prosecution witness Todd Howe kept out of Percoco's corruption trial until his client testifies.Percoco attorney Barry Bohrer argued to Judge Valerie Caproni of a "substantial risk that Mr. Howe will improperly tailor his testimony if he knows what previous witnesses have said," according to a three-page motion Bohrer filed Sunday in U.S.