A mole was placed to get my husband fired

[1Etherial]

My husband recently got a new member in his department. He has trained him and helped him with anything he needed. We went on a vacation his first in 10 years. When he got back to work there were over 100+ mistakes. He fixed everything in only a few days. Now today the new member in his department confided something very serious. He was actually hired to find everything that my husband was/is doing wrong and then tell the higher ups so they can fire him, and then lets say (Bill) would get his job. Then he began to say that he has only witnessed outnesses form the higher ups and other departments. Also there was a mistake he himself had made that they where trying to pin on my husband. At (Bills) 90 day review which is just around the corner the company is supposed to fire my husband and give Bill his position. Is there anything my husband can do? Or anything they can do together? Is this a sue-able offense for an employee?

 

[Zigner]

My husband recently got a new member in his department. He has trained him and helped him with anything he needed. We went on a vacation his first in 10 years. When he got back to work there were over 100+ mistakes. He fixed everything in only a few days. Now today the new member in his department confided something very serious. He was actually hired to find everything that my husband was/is doing wrong and then tell the higher ups so they can fire him, and then lets say (Bill) would get his job. Then he began to say that he has only witnessed outnesses form the higher ups and other departments. Also there was a mistake he himself had made that they where trying to pin on my husband. At (Bills) 90 day review which is just around the corner the company is supposed to fire my husband and give Bill his position. Is there anything my husband can do? Or anything they can do together? Is this a sue-able offense for an employee?

US law only.

In the US, there is nothing illegal about this.

 

[FlyingRon]

Presuming this is in a US state other than Montana.

They don't need an excuse to fire him unless there is some collective bargaining or contract covering his employment.
Employers are free to place spies around. It's not actionable. In fact, they could have put the new employee in the position specifically so he could learn your husbands job prior to the company firing him, without warning.

 

[cbg]

Even in Montana, if the OP's husband really is making the mistakes that are being found, that could be a legal term.

 

[Shadowbunny]

And why would your husband trust that this "mole" is telling the truth?