During trial, you should object when the opposing side attempts to introduce evidence or testimony that is legally impermissible.
Objections have two key functions. First, they prevent harmful evidence from being introduced at trial. Second, if the objection is overruled, the subject matter of the objection can be appealed to a higher court if you lose your case.
All objections made during trial must be timely. This typically means that you must raise your objection when the opposing counsel asks a question to a witness and that question will likely elicit testimony that should be barred from trial. Usually you must wait until the other attorney finishes his or her question and then object before the witness begins to answer.
The somewhat confusing case law establishing this rule reads as follows:
The rule generally prevailing in this Commonwealth is that objections to matters of evidence must be seasonably made and exceptions taken when the evidence is offered…and a party cannot of right insist upon saving an exception to evidence by thereafter seeking to have the evidence struck out or to avoid its effect by presenting the point in a motion for a new trial.
Commonwealth v. Theberge, 330 Mass. 520, 527
This is put more simply by a later SJC case:
The objection coming after the question was answered was not timely.
Commonwealth v. Roberts, 433 Mass. 45, note 6.
After you object, be ready to state your grounds for objecting–hearsay, relevance, etc. If further argument is required, it should take place on the record at side bar. However, the judge may insist on having the argument in open court in front of the jury.
If the question put to the witness is permissible but an objectionable statement is made during the witness’s answer, you should move to strike the statement. Your motion to strike should be made as soon as possible and not later than the close of the evidence.
As noted by the Appeals Court,
A party must move to strike erroneously admitted evidence prior to the close of evidence in order to preserve the issue for appeal.
Jarry v. Corsaro, 40 Mass. App. Ct. 601, 609.
Prior to trial, if litigants anticipate an argument over the admissibility of evidence or testimony it’s often best to attempt to resolve the matter beforehand through a motion in limine.
What happens after an objection is allowed? See my post: Offers of Proof in Massachusetts.