I know a guy who blew a .02 and got a DWI. He couldn’t pass the sobriety tests because he was hammered on Benedryl.
Lots of things could give similar appearances (and even odors) to being drunk, some of them serious medical conditions.
A friend who had a stroke was shunted aside in the ER lineup for hours as an 'assumed' drunk. (Former Deputy Sheriff, Volunteer Firefighter, great guy who rarely drank at all--none that night.) The brain stem stroke did not kill him, but he is a quad now.
Hopefully, the police are getting training to recognize the possibility of medical problems when the BAC (screening or breath test) comes back all wrong.