If the damage is caused in the course of private life activities such as owning a car, an animal, a building or as a parent, for example, it is civil liability. If they are a consequence of professional services, it is professional liability, also called professional civil liability.
To succeed in a civil or professional liability claim, the victim must prove 3 things: damage, fault and a link between the two. The victim must demonstrate on a balance of probabilities, i.e. there must be more than a 50% chance that what he or she says is true.
You already have liability insurance for your car and your home. They are useful in case of a claim by someone who gets hurt on your poorly maintained stairs or if your child breaks the neighbor’s window. If you are a professional, you also carry Professional Liability insurance; it is highly recommended or for some professions, mandatory.
It is said that most of the time, professionals have an obligation of means, not of results: they must take all the necessary means to render the requested services, but they are not required to be perfect; a doctor is not required to cure all his patients and a lawyer to win all his cases.
In defense, the professional tries to contradict the evidence brought by the victim. His insurer will undertake this task. The insurer first conducts an investigation to compare the professional’s version with the victim’s claims for compensation. If the investigation concludes that there is clear liability, the insurer will discuss with the professional the possibility of negotiating an out-of-court settlement, since there is no point in incurring expenses in a case that has a good chance of being lost. The insurer cannot settle at its own discretion: it must absolutely have the authorization of the professional who is, after all, defending his reputation. If there is no evidence (or not enough) to conclude that the claim is liable, the insurer will most likely want to go to trial, unless it can obtain, by force of argument, a withdrawal of the claim.