West Indies, champions in 2012 and 2016, bowed out of the tournament before the Super 12s stages after defeats to Ireland and Scotland in their first-round group, an outcome which CWI said had "caused great disappointment and frustration among all West Indies cricket stakeholders" and saw
Phil Simmons step down from his role as head coach.
Lara and Arthur - who are currently employed by Sunrisers Hyderabad and Derbyshire respectively - have been brought in as part of a three-man working group which will be chaired by Justice Patrick Thompson Jr, a high court judge at the Eastern Caribbean Supreme Court.
They have been asked to conduct "a thorough and independent review of the West Indies men's T20 team's preparation and performance" and will speak to "as many stakeholders as practicably possible" over the next six weeks, including selectors, squad members, management staff, board officials, ex-players, territorial boards and franchises and the Caribbean Premier League.
They will collate their findings and submit their recommendations as part of a final report to CWI's board of directors by December 15.
Ricky Skerritt, CWI's president, said: "It is vital that players, coaches, administrators, and all of us who love West Indies cricket, recognise that creating a sustainable learning culture, throughout the organisation, is a prerequisite for player growth and team improvement.
"Emotion-based and knee-jerk type decisions have failed CWI repeatedly in the past. I am confident that this independent World Cup review process will produce findings and learnings that should be of great benefit to our cricket system going forward."