From a legal pov, how can companies get away with mandantory drug screening as a conditon for employment?

I was curious about this...it seems like it's a violation of the 4th and 5th amendment.

Companies don't screen for say excessive alchohal use, but you can get denied a job for smoking in the privacy of your own home.

Granted there's the argument that canibus use is still illegal, but drinking is illegal if you're under 21 so would that also give them a legal precedent to screen for alcohol use also?

the employer can set conditions of employment. This includes testing for drug use and alcohol use if they want. The can check for tobacco use if they want. as long as their hiring practices do not discriminate against a class of people that have been historically discriminated against, then they can do what they want.

Remember that a private employer can hire at will and fire at will as long as it does not discriminate against people for age, gender, race and the other "protected classes" of people.

Companies can test for alcohol use. (Have an accident in a company vehicle and you can expect to be tested.)

The reason that drug testing is considered to be legal is because you accepted this in return for employment. They said: "we will hire you under these conditions." You are free to either accept those conditions or look for work elsewhere.

A requirement for many jobs is the ability to operate machinery

Employers do not want to be paying millions in wrongful death or anything else a high or drug using employee has a greater chance of causing.

It is not a violation of any rights because the employee is signing and consenting to the test ....(even though you have no choice if you want the job)

There you have it ...CONSENT !

Yes they are private companies, and you can refuse, you just willn't get the job.
The gov't started it and the supreme court at the time upheld it, based on Security, and Safety issues. That led to it being followed by the Private sector, So now You are guilty untill you prove your innocents, just another piece of them rights that have disappeared in the past 30 years.

Because you agree to take the test as a condition of employment. I don't like it either, but you have to give up your rights so you can make a living so you can pay Uncle Sam. That's the way it is these days. Man I remember when this was a free country!

simple solution. if you use drugs, dont apply. there are plenty of other people out there who dont use drugs that will take that job.

Because the 4th and 5th amendments limit governments not private businesses.

you're a free individual. YOu can take the test ; or not.

They do it to ensure the safety of all the employees.