Compliance with the prudent investor rule is determined in light of the facts and circumstances existing at the time of a trustee's decision or action and not by hindsight.
C.R.S. § 15-1.1-108
OFFICIAL COMMENT
This section derives from the 1991 Illinois act, 760 ILCS 5/5(a)(2) (1992), which draws upon Restatement of Trusts 3d: Prudent Investor Rule § 227, comment b, at 11 (1992). Trustees are not insurers. Not every investment or management decision will turn out in the light of hindsight to have been successful. Hindsight is not the relevant standard. In the language of law and economics, the standard is ex ante, not ex post.