In order to fully understand the Vietnam draft some background is necessary.
In general there is a distinction between draft avoidance and draft evasion. The former generally covers legal means to avoid being drafted, the latter covers illegal means to avoid it. For completion's sake I will cover the former first.
The song Draft Dodger Rag by Phil Ochs covers pretty much all types of deferment a draftee could hope for, in the chorus alone:
Sarge, I'm only eighteen, I got a ruptured spleen,
And I always carry a purse.
I got eyes like a bat, and my feet are flat, and my asthma's getting worse.
Yes, think of my career, my sweetheart dear, and my poor old invalid aunt.
Besides, I ain't no fool, I'm a-goin' to school,
And I'm working in a defence plant.
In the song the singer is angling for a draft deferment based on a 4-F classification (unfit to serve, for either physical health or moral reasons), although the last three lines dealt with more appealing reasons for deferment, being a student or having dependants. It's a very interesting song. Ever since World War I there were laws against counselling people on how to avoid being drafted, but Ochs got away with this song because of its satirical nature. The song, in its joking way, offers quite a bit of advice on how to avoid being drafted: make sure you seem gung ho and enthusiastic about the war so you're not making yourself suspect, while also having numerous excuses related to both physical and moral health.
The draft was active between 1940 and 1973. With the exception of World War II and the Korean war draft quotas were generally very low. This generally made draft boards very lenient with 2-S (student) or 3-A (hardship) deferments. The former basically depended on going to college, as a full undergrad program generally made the draftee too old to draft on completion (not formally, but they were often passed over in favour of younger draftees). The latter hinged on proving that you had dependants. You could be the only male in your family capable of earning an income, or have a young wife and child. 3-A deferments for paternity weren't always a sure thing. On September 25, 1951 newly married men no longer automatically qualified for deferment if they didn't have a child, and from July 11, 1953 onwards paternity deferments were completely done away with. The 3-A deferment for paternity was reinstated by president Kennedy in 1963, but once again ended by president Nixon in 1970 as draft boards struggled to meet quotas.
These were the basic methods of draft avoidance. Let's move on to evasion.
One of the evasion methods most commonly associated with the Vietnam War was moving to Canada. The reason this was so popular was not just the fact that Canada was a road trip away, but that the extradition treaty that existed between the United States and Canada at the time didn't cover desertion as a crime that someone could be extradited for. On top of that Canada had a large network of anti-war groups who would help accommodate these draft migrants. There was even a Manual for Draft-Age Immigrants to Canada published. Now moving to Canada generally meant that the draftee could avoid going to Vietnam, but it had a social stigma associated with it that could negatively influence career prospects in the future. On top of that, if a draft evader were to return to the United States he could still be prosecuted. In 1974 president Ford introduced an alternative amnesty program. Jimmy Carter actually campaigned on a program where any draft evader could get a pardon if it were requested, a promise he fulfilled the day after taking office.
Another invasion method that was common was getting oneself arrested for a crime that carried jail time. Statistical analysis for prison records for the states of New York and Georgia has shown that young men who were likely to be drafted were overrepresented in the prison population between 1965 and 1970. Of course dodging the draft this way, like the Canada route, would have a significant impact on the remainder of the person's life, via having a criminal record.
A less common method of evading the draft was gambling on the bureaucracy. Depending on how the local draft board was organized it would be possible to appeal the draft board decision, sometimes several times, to the point where people choosing this route hoped that either the appeal process could be drawn out to the point where either the war was over or they were too old to be eligible, or that somewhere along the line the paperwork would get lost or misfiled.
Now let's say you simply stay put and refuse to turn up. You either just ignore all the mail you get or you actively protest by burning your draft card. Draft evasion is a federal crime, and thus prosecuted under federal court. Under the Selective Service Act even failing to register for the draft is a federal offence. If you were found guilty the penalty was up to five years in prison and/or a fine of up to $10.000. As the war wore on and protests became more public anti-war protesters would sometimes deliberately allow themselves to be arrested, then use the trial as a public platform to speak out against the war. These days the penalty for failing to register is up to five years in prison and/or a fine of up to $250.000, although there haven't been prosecutions for this since 1986.
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