Dr. Haledjian, I presume.....?!

Dr. Haledjian, I presume.....?

Driving through a dilapidated neighborhood at midnight, Dr. Haldejian abruptly stomped on his brakes. His headlights had illuminated a man lying on the sidewalk. The man was still breathing, though strangulation marks on his neck indicated the sleuth's sudden arrival had scared off the assailant in the nick of time.

The street was deserted till an elderly man stepped from the door of a decaying building nearby.
"Why, it's old Keyes! I knew this would happen. I warned him!" "Warned him about what?" demanded Haledjian. "About going around jingling his Confederate half-dollar. I'm Stevens. Keyes and I have lived across the hall from each other for twenty years. Ten minutes ago I heard him go out - he jingles that half-dollar all the time, as if inviting somebody to rob him." "Is the half dollar valuable?" "It is one of four made in 1861, and its worth about $5,000," said Stevens. "Keyes kept it as a good luck charm. I've told him to be careful. Is it stolen?"

Haledjian refused to permit a search on the sidewalk. At the hospital, however, the coin was found in Keyes' right trouser pocket. Haledjian telephoned Inspector Winters. "The only other items Keyes carried were two handkerchiefs and a leather wallet containing a dollar bill," said the sleuth. "I suggest you arrest Stevens at once!"

How come?

to be jingling coins you need more than one. If he only had one, them Stevens was lying.