Evidence against disability case

[Ohwhy]

I live in Michigan and the case was filed in Texas. I know a person who is tryin to sue a transportation service for disability because they crashed while they were in the vehicle. Now my concern is that this person is saying that they are disabled and cannot work. This is not true. I work with this person and they are clearly not disabled and brag all the time about how they are not. My question is; can I legally videotape this person at work and give it to the transportation company to use against this person. I do not think it is right for this person to be doing this. If I can how would I go about doing this!