In 1977, President Jimmy Carter, on his first day in office, followed up immediately on his campaign promise. As a result, he pardoned hundreds of thousands of men who had dodged the draft. They had fled the country during the Vietnam War or had simply failed to register with the Selective Service boards. Though today this sounds like a no brainer, it garnered a lot of criticism at the time.
Veterans felt that a blanket amnesty was not a great idea, they disapproved of letting unpatriotic lawbreakers go free. And on the opposite side of the argument, President Carter received criticism for not pardoning the deserters, dishonorably discharged or the violent anti-war demonstrators. Gerald Ford, the previous President, did offer some pardons to various draft dodgers. Carter went much further as he attempted to heal the wounds of the Vietnam War, by setting no conditions for the pardon. Though as mentioned before, certain individuals were excluded.
During the late 1960s to 70s, over 100,000 Americans went abroad with the main aim to avoid being called up to fight. Around 90 percent were in Canada, which at first was quite controversial, though they were accepted as legal immigrants after some time.
Hundreds of thousands hid at home or changed their identities. Not to mention, there were also over 1,000 military deserters who ended up in Canada. While the authorities in Canada did at first announce they would be deported or even prosecuted. In practice, they were left alone and not bothered. Canadian border guards were explicitly told to not ask many questions.
After the war, the federal government continued to prosecute draft evaders. In total 209,517 men were formally charged and another 360,000 were found in violation but never charged. Before the blanket pardon, they all would have faced prison sentences if they ever chose to return to the United States.