Answer Or You Lose.
In Colorado, people living in-state have 20 days to file an answer (or responsive pleading) to a properly served summons and complaint. Those residing out of state have 30 days. This is a deadline and under Colorado law, failure to comply can result in a default judgment against you, meaning you lose automatically by forfeiture.
This is why you should engage an attorney as soon as you are served with a lawsuit. Unless you intend to represent yourself, which is normally not a great idea, your lawyer will need plenty of time to get up to speed on the facts in your case and develop counter-claims and defenses. Do not go shopping for a lawyer two days before the deadline.
What If You Are Defaulted?
If you are served with a default judgment, there are very few circumstances in which you can have the default set aside. These include known military service, for example, and circumstances which show extreme hardship, no-fault, attempted compliance, and no prejudice to the other party if the default is set aside and the matter revived for trial. Still, it is a rare thing and cannot be counted on. If you have rock solid reasons, like you were on deployment to Afghanistan, you may succeed. But we have had adversaries try to set aside our default victories by saying "Your honor, I didn't answer because I just thought they were trying to scare me." That didn't work. Neither did "Gee, I didn't even know about the suit!". Lawyers use process servers who swear in writing that they have given copies of the suit to the proper parties. If you have been properly served, your plea of ignorance will get you nowhere.
Why There May Be Hope...
If you have missed the filing deadline for responding to a lawsuit, it may be possible that the other side has not yet filed for a default judgment. Or if they have, but the court has not ruled on it, it may be possible to file an appearance and submit your answer anyway, hoping that the court decides not to be strict and let you make your defense. Surprisingly, courts tend to be somewhat lenient in this regard, and can even scold an attorney that demands a default the day after a deadline has passed. Of course, you will want to have an attorney carefully prepare the filings so as to insure that they make all of the special arguments and justifications relating to the delayed appearance and response. But there is some hope even if you have missed the answer deadline. If you are in this situation, call us or another litigation lawyer immediately. Do not wait.