Cowen began his legal career as a
law clerk for Judge Walter Conklin of the
New Jersey Superior Court from 1958 to 1959 before becoming a private practice attorney licensed in the State of New Jersey from 1959 to 1969. Cowen also served as an Assistant county prosecutor for the
Essex County, New Jersey Prosecutor's Office from 1969 to 1970 before joining the New Jersey Attorney General's Office as a deputy state attorney general from 1970 to 1973 before becoming the director of Ethics and Professional Services in the Administrative Office of the United States Courts for New Jersey from 1973 to 1978. Cowen served 11 years before assuming
senior status on September 4, 1998. He resumed active status briefly in July 2022 for the purpose of resolving J. M. v. Summit City Board of Education. ==References==