First, it's important to understand that all the laws that have been passed in Canada, whether in the House of Commons or in the Quebec National Assembly, have been passed in good faith. Elected representatives really wanted to opt for the best solution.
Second, the problems arise when you enforce those laws. For example, some people can afford to hire a lawyer, who will find a procedural error. Despite what our colleagues say, blood alcohol tests are currently calibrated so that people aren't convicted in spite of dangerous blood alcohol levels. The lawyer doesn't question the blood alcohol level, but rather the procedure. Did the police officer put a comma in the right place? Did he do this or that? If a police officer is humiliated five times in court, the next time, he closes his eyes if rich people are involved.