Employers aware of Drink Driving Employee

Convicted Driver Insurance
I have found myself in a bit of a troublesome situation at work. I have caught a fellow employee drinkinging throughout the working day. I have informed her manager and senior management and they have started disciplinary proceedings. I have subsequently found out that this is a regular occurance and that she has an alcohol problem. What troubles me however is that they are content for her to drive to and from work (her own car). Surely if they are aware she is drunk they have a responsibility to stop her. I have threatened to call the police but have been told to back down by senior management as I am being over zealous. Where do I go from here? Does the employer have any legal responsibility?
Personally I am going to give them a day to sort it out then report her, and damn the consequences. Advice greatfully received.
It is a criminal offence to aid and abet another to drink and drive. I deal with lots of people who give their car keys to a person that they know to be drunk and allow then to drive their car. Those people can be convicted and sentenced to points or a ban.

In theory, I suppose, this could stretch to an employer who allows an employee to drive, knowing that they are drunk, although I have not come across this specifically. It is probably highly unlikely that the police would actually prosecute an employer in these circumstances.

I don't beleive that you personally have any liability as you are not permitting them to drive, although you know it's happening. Simple knowledge of an offence does not impute any criminal liability upon you.

There may be other considerations for the employer from an employment law point of view but this is not my personal area of specialism.
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