Jerry Buting, one of Making a Murderer subject Steven Avery's original lawyers, recently told Rolling Stone that "internet sleuths" (obsessed fans) found evidence in a photo of victim Teresa Halbach that lawyers missed. Buting hopes new evidence like this could change the entire case, by opening the possibility of another trial. 

Internet sleuths found key evidence that lawyers missed in this photo.

This new key evidence is literally "key" evidence. The picture, shown frequently on the news and in the Netflix docu-series, apparently shows Halbach holding a key fob with several keys. This is in contradiction to the one lone key police allegedly found when searching Avery's bedroom on November 8, 2005 (three days after finding nothing on their initial search on November 5, interestingly). 

Halbach is holding a ring with several keys, not just the lone key police found.
 Take an even closer look.