What Happened?
Several weeks ago, the Department of Justice (DOJ) began an investigation of certain colleges that offer early decision programs, some of which include Amherst, Williams, Middlebury, Wesleyan, Wellesley Grinnell, and Pomona. These colleges, along with others, were contacted by the DOJ and asked to ‘preserve’ communications relating to students who applied to their Early Decision  programs.

What are the effects?
In general, ED benefits both the applying student and the college; students are given early admission to their top-choice college while the school increases the percentage of admitted students who enroll. However, the emerging news about information sharing between schools has caused some to feel  the practice could inspire a “conspiratorial conduct” similar to that of 1991’s Overlap Group (a group of elite colleges that got caught in violation of antitrust laws due to standardization of financial aid). On the other hand, some admission officials address these accusations by referring to the Common Application waiver, which entails the sharing of student information.

What are the implications?
There are other facets of the early decision program this investigation raises. From a legal perspective, the majority of students applying to college are under 18, and therefore cannot sign an official contract. Thus, these early decision “contracts” are grounded on an ethical basis rather than legal one. Nevertheless, while there are no immediate punishments for students who back out of early decision agreements with colleges, colleges that get reneged by ED students can accept fewer  regular admission students from that same high school. Essentially, if someone from your high school backs out of an ED agreement, it is possible that you could be negatively affected if you applied to the same college RD, even if you had nothing to do with the initial offense. Additionally, the students that break ED contracts could also be put on a sort of “blacklist” shared between other schools.
One of the commonly alleged claims against early decision programs is their favoritism of more affluent applicants. Often times wealthier applicants do not need to explore multiple colleges and compare financial aid packages to the same extent poorer applicants might. These financially worse off  applicants may need to explore a wider variety of options (for example, compare financial aid packages) and forgo an opportunity to commit ED while their wealthier counterparts do not have to worry about negotiating finances. Thus, the ED program can be seen as a filter that affluent applicants can pass through to get an advantage.
Amid the speculations and concerns, some anonymous admission officers have assured that the information being shared between institutions is only of the aggregate category (i.e. compiled stats with no identities.) Whether or not the data is specific, information is being communicated between the aforementioned colleges, and the full implications for future college admissions processes have yet to be seen.
References:
https://www.nytimes.com/2018/04/10/us/politics/justice-department-probe-college-early-decision.html
https://www.npr.org/2018/04/13/602288585/justice-department-investigating-how-colleges-use-early-decision-admissions
https://www.insidehighered.com/admissions/article/2018/04/09/justice-department-starts-investigation-early-decision-admissions