One must complete due diligence before using an image. Sometimes it is as simple as seeing if the image falls under the Public Domain or under a Creative Commons (CC) License. If the image is not in the Public Domain you will need to look at the Fair Use Act to decide if the use is allowable. Below are some questions that may help you determine the legal use of an image. Although, keep in mind this is not a legal answer, only a tool to help you determine the allowable use of an image.
1. Is the work covered by copyright?
Does it fall in the Public Domain? (before 1923) Yes, you can use it.
Does it have a CC license? You must determine what the CC license allows.
2. Is your intended use permitted?
Is there a copyright exemption for your intended use?
Is it licensed through your institution and provide use?
Does the CC license allow for your use?
3. Does your intended use fall under Fair Use?
Have you answered all four Fair Use factors and does the use meet all criteria? Not Sure, use theArtstor Copyright Checkpoint. (Note: this is not legal information or advice)
4. Can you get permission?
Get a verbal or written notice from the creator to give you permission to use the image. Written is always better.