 The Constitution of 1867 overturned the registry test oath embedded in the 1864 constitution.The issue of slavery may have been settled by the new constitution, and the legality of secession by the war, but this did not end the debate.On April 14, 1865 the actor John Wilkes Booth assassinated President Abraham Lincoln at Ford's Theatre in Washington, D.C. Booth was born in Harford County, Maryland, a northern county on the Pennsylvania border, which had few slaves.