John T. Gauthier, a former president of defense contracting companies in the Washington area, died May 30 at a hospital in Cerritos, Calif. He was 85.

The cause was pneumonia, said his son Paul Gauthier.

Mr. Gauthier lived in the Washington area from 1954 to 1984, working as a certified public accountant with Page Communications for three years and then as president of Datronics Engineering Co. defense contracting. For several years, he also was president of as many as 20 companies spun off from Datronics.

John Thomas Gauthier was born in the Bronx, N.Y. He graduated from Fordham University in 1950 and received a master’s degree in business administration from George Washington University in 1954. He was a 1956 graduate of Georgetown University law school.

He moved to Florida from Bethesda in 1984 and had been in Cerritos since 1996.

His marriages to Katherine J. Doyle and Marie Noell ended in divorce. In 1996, he married Anita Wu.

Besides his third wife, of Cerritos, survivors include two sons from his first marriage, Peter Gauthier of Arlington County and Paul Gauthier of Frederick; a stepson, Alex Wu of Cerritos; a sister; and four grandchildren.

— Bart Barnes