A general review of the manner in which lawsuits can be brought against government agencies and employees precedes analysis of the Supreme Court's decision in City of Canton v. Harris in which the general principles of "failure to train" lawsuits were established. The discussion also considers the manner in which those general principles apply to firearms training. Before a claim against a department's training program can be established, there must first be a constitutional violation. Additionally, it must be established that the officer's training was deficient and that the deficiency was due to the department's policy or custom and also that a causal connection exists between the deficient training policy and the constitutional injury. 30 footnotes