Casper was ordained in 1963 in the Pueblo Diocese in Colorado. He was said to have taken a “leave” for undisclosed reasons. In 2003, the Diocese of Rochester reportedly stated that Casper should not have been practicing as a priest for at least three decades. This was after two brothers accused Casper of sexually abusing them during the 1970s. One of the brothers has alleged that the abuse began while Casper was at the St. Patrick Church in Albany, although the Diocese of Albany claims it has no record of Casper serving there. As the Times Union reported, even though Casper apparently said Mass in Albany and elsewhere for nearly 30 years, both the Diocese of Albany and the Diocese of Rochester contend Casper did not have their authority to act as a priest in upstate New York.