Is it Legal for Company to deduct pay for breaking internal rules?

Not sure of how else to phrase this question.

I'm almost positive that this is grossly illegal but I'm not really familiar with the legal terminology involved here.

Company (contracted Security, building has their own security team but contracted out the rest of the work to the company I currently work for.) has attempted to begin implementing new rule where employees are fined for breaking rules such as being on their phones during work hours or not being at certain posts when asked.

I could see being written up or fired being applicable, but apparently the company has decided that for each infraction that they would deduct $150 from the employees wages in doing so.

That cannot be legal I'm sure but I'd like some help on the exact clarification needed to seek better legal advice.

This is in the United States and state of Texas for better clarification.