Short answer. Yes. Under Rule 28, Section 1 of the Rules of Court, when the mental or physical condition of a party is in controversy, the court where the action is pending may, in its discretion, order that party to submit to a physical or mental examination by a physician.
What the law says
In an action in which the mental or physical condition of a party is in controversy, the court in which the action is pending may in its discretion order him or her to submit to a physical or mental examination by a physician.
Rule 28, Section 1 — When examination may be ordered. Read the full provision →
When the power exists
The section reads: In an action in which the mental or physical condition of a party is in controversy, the court in which the action is pending may in its discretion order him or her to submit to a physical or mental examination by a physician. Two requirements do the work. First, the party's condition must be in controversy — genuinely at issue in the case, not merely of curiosity to the opponent. Second, the decision rests in its discretion: the court weighs whether an examination is warranted, and nothing in the section obliges it to order one.
What "in controversy" looks like
A condition is in controversy when the case itself turns on it. A claim for damages arising from physical injuries puts the extent of those injuries at issue; a petition that rests on a party's psychological condition makes that condition a fact to be proved; a defence that a signatory lacked capacity puts capacity in play. By contrast, litigation does not open a party's health to inspection generally — a collection suit or a boundary dispute gives the opponent no path to a medical examination, because nothing in such a case makes anyone's body or mind a fact in issue.
The limits of the section
The examination the court may order is one by a physician, and only a party to the pending action can be made to submit — the section does not reach witnesses, relatives or bystanders. It applies in an action already pending before the court; it is a discovery tool inside litigation, not a free-standing way to compel a medical assessment of someone. And because the power is discretionary, the party asking for the examination must persuade the court that the condition truly is in controversy and that examining it will matter to the outcome.
If you are on either side of the motion
If you are resisting an examination, the ground to argue is that your condition is not genuinely in controversy — that the case can be decided without it, or that the request is harassment dressed as discovery. If you are seeking one, be ready to show precisely which issue in the case the examination will illuminate. Either way, the pleadings matter: what has been alleged about a party's mental or physical state is usually what puts that state in controversy, so read the complaint and the answer before assuming the court can, or cannot, make the order.