Generally speaking the reliability of a news source is based on their standards of journalism rather than on whether they are mainstream or independent. As long as a news or information outlet adheres to ethical journalistic practices and standards, that news organization can be seen as reliable. Some of these standards include but are not limited to:
- Accuracy and factual reporting
- Following proper investigative methods
- Avoiding outright slander and libel
- Proper attribution of sources ( when harm will not come to the source)
- Making corrections to discovered errors
- Adhering to other set journalistic ethics and standards
Violation of these standards happen in both mainstream and independent publications, so both mainstream and independent news organizations can be seen as either reliable or unreliable based on their practices. However as general rule, due to longer track records and more credibility with the public, mainstream news sources are usually perceived as being more reliable ( even though this may not always be the case).