The Union's draft of 1863-1865 allowed for men of military age subject to enrollment for it, to pay a 300 dollar commutation fee or could provide an acceptable substitute to serve in one's place.
Examples from some of the drafts. Very few of the men drafted actually ended up serving. Besides paying the commutation, or providing a substitute, many men did not pass the physical examinations, etc. Another large number "failed to report" at all or were what were called "draft dodgers."
The men that failed to report, or otherwise abide the draft laws, were called "draft dodgers" during the war:
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If captured they were subject to various penalties, and could not vote, etc.
Gallipolis Journal, OH, Sept. 7, 1865.
Conscientious objectors could report as such, and be enlisted for non-combat service. Or could make a donation of 300 bucks to benefit sick and wounded soldiers for an exemption from a particular draft.
At the conclusion of the war, there were over a million men enrolled for the drafts who had not been called or held to performing personal military service. Postwar calculations show less than 300,000 men actually drafted, the majority of them either paying the commutation fee or hiring or by other means providing a substitute to join in their place.
Grover Cleveland was enrolled for the draft, and drafted and notice appeared in the Buffalo, NY papers on August 5, 1863:
As mentioned in the previous posts, he was not held to personal service by the draft, as a substitute entered the service in his place.
Always heard rich man's war poor man's fight, for confederates, I wasn't aware that that Yankees could hire a sub too. If so are there other political leaders that hired subs during the war .
The Union draft differed from the "conscription" employed in the Confederacy, and eventually, when the South would receive no more substitutes, and all men of military ages 17-50 were eventually ordered into active service, unless otherwise exempted by law: the exemptions often based on property ownership; Thus the Confederate soldiers lament:
Though he was overage for draft enrollment, President Lincoln hired a substitute in 1864, John S. Staples, who served with the 2nd District of Columbia Volunteers. It was said he did this to encourage the hiring of substitutes to aid in filling the ranks, instead of merely paying the cash commutation fee.
There were insurance pools which one could join for fees, which would guarantee providing and paying for a substitute, without the payee having to wrangle with the subject, and being raked over the coals by substitute brokers AFTER being drafted.
The Chicago Draft Insurance Company, for example, advertised that draft enrolled men who joined would be guaranteed a substitute if drafted (evidently from a pool of men hired by the insurance company for the purpose), saving the draftee money, where after the draft, on their own, they would be subject to exorbitant fees, etc.