Issues can arise with respect to medical records when the employer has access to them in connection with the administration of benefits and payment of healthcare claims. If an employer has access to an employee's medical records for this purpose, it doesn't necessarily give the employer the right to access to the records for all purposes, or to share them with anyone else. Employers should be very careful in this area and treat medical records as confidential.
Normally, employers also own their e-mail software and are at liberty to monitor their own equipment. No notification is required. Some union contracts may limit the type and amount of monitoring or require notification of monitoring.
Usually, an employer can videotape employees, but it depends upon where the camera is set up. Employers can usually only tape in an area that monitors work activities. People expect more privacy in a bathroom, changing room or locker room, so it's usually illegal to videotape those areas without telling employees.
Searching desks, lockers and other places where there may be an expectation of privacy may get more complicated. In some states, if an employee takes steps to secure the privacy of a locker, the employer might not have the right to search the locker. In other states, the employer may have an absolute right to search a locker.
The bottom line is that an employer has a fair degree of control over the right to privacy of employees while they're on the job and using the employer's property. But the degree of control isn't absolute. Any employer policies on these issues should be clearly written and made known to all employees.