Are written by justices who agree with the outcome or the decision in a case but disagree with the logic or the reasons for that decision. In short, although the outcome is acceptable to the concurring justice, the explanation for that result requires a separate opinion that outlines different reasons for the result.
A concurring opinion may clarify the outcome in the case and strengthen the result. Certainly it explicates the reasoning of the individual justice or justices. This is advantageous to the justice, and it may provide some comfort to the future litigant who relies on that separate opinion rather than the majority opinion for precedent. Such an opinion may also assist the development of legal doctrine if the majority opinion is unclear or confusing. However, a concurrence can also detract from the impact of the majority opinion, and even the threat of preparing such an opinion can cause the majority opinion writer to adjust the majority opinion to accommodate the position of the possible concurring justice.
Traditionally, justices were reluctant to invest their time and energies in such opinions since the result in the case was acceptable to them. However, recently there is an impression that justices are concurring with separate opinions more frequently. There has been some increase in the numbers and the ratio of majority opinions to concurring opinions at times during the past two decades, but these figures are not any higher now than several decades ago.
The potential problem, which began to surface more frequently in the past two decades, is the absence of any majority opinion. This is the extreme consequence of concurring opinions, as more and more members in the majority write a separate opinion. Such a proliferation of opinions leads to a lack of clear precedent and borders on the practice of seriatim opinions rendered by the Supreme Court when it began functioning in 1789. This approach, however, has not been predominant.
See also Plurality Opinions.
— William McLauchlan




