Affidavits are frequently used in the preliminary stages of court proceedings, but only rarely are they admitted as evidence at trial. Affidavits are used in emergency situations when time is short and the need for court action is great, such as with emergency protective orders. Affidavits are also used to increase court efficiency by identifying those situations where the facts are not disputed. If there really is no disagreement between the parties about what happened, then there may be no genuine need for the time and expense of a full-blown trial, and a motion for summary judgment may be justified.
Regardless of the use to which an affidavit may be employed in modern legal practice, the characteristics of a well-crafted affidavit are the same throughout. I am indebted for this to an excellent article published in the January, 2010, issue of the South Carolina Lawyer by attorneys Christopher Kelly and Laura Simons, Attacking Affidavits: Maintaining the Integrity of the Process, and a 2008 memorandum of law by Andrea Kuperman, Admissibility Requirements for Summary Judgment Affidavits. In general, an affidavit may be attacked for the following reasons:
- If the formalities of a sworn statement are lacking. An affidavit should show that the person signing the statement was first sworn to an oath that the statements are true and then be at risk for the penalties of perjury if they are not true.
- If the person making the affidavit is not a competent witness. A competent witness is capable of understanding the serious nature of a sworn oath. A very young child or one suffering severe mental disability may not qualify as a competent witness in general. Likewise, one who is profoundly intoxicated or under the influence of powerful medications may be temporarily incompetent to make a meaningful oath. An affidavit should state facts that establish the affiant’s competency.
- If the affiant is an attorney for one of the parties. In most jurisdictions it is a violation of professional ethics for an attorney for one of the parties to be a witness. I can think of no good reason why an offer of evidence by way of an affidavit should be an exception to this. This is not an issue of competency.
- If an affidavit is to be used in a legal proceeding, it should contain specific statements of fact that would be admissible as evidence at trial, just as if the affiant were testifying as a live witness in court. All the rules of evidence concerning firsthand knowledge, opinion, speculation, hearsay etc. may come into play.
- In a similar vein, the statements of fact in an affidavit should be specific. Although vague and conclusory statements of ultimate facts may be appropriate for notice pleading, they are not useful as proof.