I have a bit of a problem with this amendment. It seems to me that you can already do what you want and that this would only add options for abuse.
My understanding of the way you have drafted Bill C-32--and I'm not sure why you'd bring an amendment later--is that if the police suspect a person has been impaired driving, they can run them through the tests. The amendment says they just have to suspect that they have had alcohol and that they drove a car. There's a good likelihood in modern society that anyone has driven a car within the last three hours. He doesn't have to suspect he was driving the car while impaired, which was your original draft; he just has to suspect he was driving, which could force almost anyone into these tests once they've had alcohol. That doesn't seem to make sense. It seems to me that could be open for abuse. The way you have it written in the first bill, the police officer can subject a person to the test if they think they were impaired driving.
As well, I'm not sure why you added this after you drafted the bill.