Now, comes another reason to be skeptical of Donald Trump's supporters who claim thousands of dead people voted in Michigan.
The BBC took a sampling from a list of about 10,000 people in Wayne County who were supposedly dead and voted by absentee ballot. The list was from a Trump-supporting activist.
Here's what the BBC found:
There's a fundamental problem with this list of 10,000. With an exercise like this you are going to find false matches - somebody born in January 1940 voted in Michigan in the election, and there was somebody born somewhere else in the US in January 1940 who has the same name and is now dead.
To test the list, we picked 30 names at random. To this we added the oldest person on the list. Of this list of 31 names, we managed to speak directly to 11 people (or to a family member, neighbour or care home worker) to confirm they were still alive.
For 17 others, there was no public record of their death, and we found clear evidence that they were alive after the alleged date of death on the list of 10,000. A clear pattern emerged - the wrong records had been joined together to create a false match.
"I may be 72," Maria Arredondo from Michigan told the BBC, expressing surprise she was on the dead list. "But I'm alive and breathing. My mind is working fine and I'm healthy."
In the sampling of 31, the BBC did find some voters who were actually dead.
One included a woman who supposedly died in 1977. But the reality was she was alive when she returned her ballot, but died after that. The network said it could not determine if the vote was counted. Michigan law prohibits votes from being counted if the person dies before election day.
In two other cases, two men on the list of 31 had died long before the election, but votes had been cast in their names with zip codes and birth dates that matched. The BBC found that the men had sons with the same name currently registered at the same address.
In one case, a local election official said the vote of the dead person was counted, but there was no record of the son voting. In the other instance, the son voted, but it had been recorded as the father's due to a clerical error.