Sexual Harassment Evidence
I get many calls to my Chicago office about what constitutes evidence of sexual harassment. There are many types of evidence. Direct testimony, where a person testifies about what he or she heard. There are email, text messages, and voice messages (it is illegal in Illinois to record someone without their permission, but if a person chooses to leave a voice message they are consenting). Sometimes the person doing the sexual harassment will give gifts, send cards or letters via the post office and may call the person during non-work hours. I can get the telephone log to show the calls were made and there usually isn't a business reason to call someone at home late at night or after work. This would constitute a hostile work environment.
If your boss or the person committing the sexual harassment only does it one on one, a good technique to utilize is to send the person an email, memorializing what he said to you and see if he responds. So if he said he would like to take you out and do xyz to you, send him an email and say something like you caught me off guard in the hall today, do you really want to go out with me and do xyz? You are not entrapping him but rather just memorializing what he said and seeing what his response is. At the end of the day if you file a complaint of sexual harassment, the burden is on you to prove your case so it is very helpful if you have some evidence.