Colorado Paternity: Biology Balanced vs 3 Legal Presumptions

Father snuggling with a laughing newborn baby.

Legal Paternity in Colorado

Did you know that Colorado paternity law makes it possible for a man to have to pay 19 years of child support for a child that he didn’t conceive? Or that it’s possible to have spent 10 or more years caring for a child you believe to be yours, only to find out that some other man sired the child, and then under Colorado paternity law, lose your parenting rights? These things can happen, and understanding the laws of paternity can help protect you from these awful outcomes.

DNA Helix from Colorado paternity test
DNA Helix

Ever since you first heard about the birds and the bees, you’ve probably been aware that the mechanics of reproduction dictate that under present medical science, every person has a biological mother and a biological father. One sperm cell from one particular man plus one egg cell from one particular woman… most people assume that the laws of paternity are just like the laws of biology.

As a lawyer who deals with Colorado paternity cases, I can’t tell you how many conversations I’ve had where a person says, “we took the paternity test, so that’s that.” The laws of paternity are considerably more complicated than most people assume – taking a paternity DNA test is the beginning of the inquiry, not the end.

Legal Paternity in Colorado conveys certain rights and responsibilities. Chiefly, if you are a child’s legal father, you have the legal right to make parental decisions, to sue for custody/visitation, and you will have the responsibility to care for the child whether in your own home, or via child support. Biology alone does not confer these rights in a Colorado paternity case. 

So how does legal paternity get established in Colorado? In short, a man becomes a legal father by satisfying one of the presumptions of paternity identified in Colorado paternity statutes (Colorado has adopted the Uniform Parentage Act). There are a few legal presumptions, and if more than one man fits into the presumptions for any given child, the Colorado judge will decide who should be the legal father based on the best interests of the child.

Presumption of Marriage

The first Colorado paternity presumption is the presumption of marriage. Namely, if you are married to a woman at the time of the child’s birth or conception, you are presumed to be that child’s father. This presumption has a long history. In the days before blood tests the old common law adage (stretching back to Roman law) was “the mother is obvious, the father is her husband.” The presumption is codified in by C.R.S. 19-4-105(1)(a).

For a majority of children born in the U.S., this is how paternity is established. Although marital infidelity exists, most married couples seem to trust each other, and the husband is assumed to be father most of the time. Usually, this system works very well, but problems can arise especially when married couples split without divorcing.

In this day and age it is relatively common for people to marry young, and after it is clear things aren’t working out, for the couple to go their separate ways without ever officially divorcing. Years later, having given birth in a new relationship, the mother may be surprised to learn that her husband (who she hasn’t touched in years) is still a presumptive father.

Colorado paternity law also includes legal presumptions related to marriage that could fairly be called “sub-presumptions” of the marital presumption. These rules are contained in C.R.S. 19-4-105(1)(b) & (c), and pertain to “attempted marriage”. This concept applies to situations where people may have reasonably thought they were married, but weren’t for whatever reason. For instance, if a person got married thinking their divorce had been finalized when it hadn’t, then the second marriage would be invalid. However, such an invalid marriage would probably be considered an “attempted marriage” under these rules.

Hold-Out as Father Presumption

The second major Colorado Paternity presumption is called a “hold out” or a psychological father. The key to this presumption is that a man takes the child (usually with the mother) into his home, and treats the child as his own natural child. The purpose of this presumption is to avoid separating children from the only “parents” they know, even if not biological, and it has the additional effect of protecting men who have formed a psychological bond with a child.

A typical scenario that might fit this presumption is when a guy with a live-in girlfriend finds out that there was an affair, and the child was sired by another man. All the same, this guy has bonded with the child and wants to be the legal father. The hold out presumption allows him to make this argument and is found at C.R.S. 19-4-105(1)(d).

Presumption of Biology

The third major presumption is the biological presumption – despite being the most important in many people’s eyes, it’s just another presumption in the eyes of Colorado paternity law.

In short, if you are biologically the father, you have a presumption in favor of paternity. This presumption is codified in C.R.S. 19-4-105(1)(f). The biological presumption attaches when a paternity test done by an accredited lab shows that there is a 97% or higher probability that the man in question is the father of the child. 

In any Colorado paternity hearing, the law states that the parties to the case shall be the mother, as well as any men who are either alleged or presumed to be the father of the child. C.R.S. 19-4-110. This means that all men who qualify under one of the above mentioned presumptions must be a part of the case, as well as any men who are alleged to be the father. “Alleged” in this case means a person who could be a biological father, and generally speaking that means any man who the mother had sex with around the time of conception. However, courts will excuse this requirement if there is a qualifying blood test identifying the actual biological father. 

The courts have ruled that there is no hierarchy among these presumptions. They are all equal and could therefore serve as the basis for legal paternity. N.A.H.1N.A.H. v. S.L.S., 9 P.3d 354 (Colo. 2000).

As mentioned above when there are competing presumptions, the court will decide who gets to be legal dad, based on the best interests of the child.

Skip the Hearing: Sign an Acknowledgement of Paternity

Most of the time, when there are no doubts as to who dad is/should be, that man is placed on the birth certificate from day one.

Colorado Voluntary Acknowledgment of Paternity
Colorado Voluntary Acknowledgment of Paternity

When children are born in a Colorado hospital, staff will take information to go on the birth certificate. The mother will be asked if a father is to be listed. If she tells staff to list her husband, that man will be added without any fuss. If the mother is unmarried, or names a man other than her husband, that man needs to sign a State of Colorado Voluntary Acknowledgement of Paternity in order to appear on the birth certificate. This form is fairly straight-forward. If a man other than the mother’s husband is named, the mother’s husband also needs to sign the acknowledgement for it to be valid.

An acknowledgment is technically a presumption under C.R.S. 19-4-105(1)(e). However, once the form is signed, it becomes more than that, as it’s essentially binding after 60 days. C.R.S. 19-4-105(2)(b). So if you are a prospective dad being asked to sign an acknowledgement, be very careful. This attorney has seen cases where a man signed the form to find out during a break-up that the child wasn’t his, only to be on the hook for child support several years later. If you have doubts, remember paternity tests are easily obtained, and the court is prohibited from discriminating against a father who “just wanted to be sure” with a paternity DNA test before accepting paternity.

If no man is initially added to the birth certificate, Colorado legal paternity will be established in a judicial proceeding with reference to the paternity presumptions. Either mom or any potential father can file for a paternity determination. Once this determination is made, the declared father will have his name added to the birth certificate as if it had always been there.

FAQ – Colorado Paternity Presumptions

Can I do a home DNA test?

When a couple is unsure whether a man is the father of a child, they may take a home DNA test. While the results are not legally conclusive in a Colorado paternity hearing, as long as neither parent disputes the test result, no formal paternity DNA test would be ordered.

How much is a paternity test?

A home paternity test, where the parties and child do the swabs at home and mail them to a lab for testing, costs between $100 – $150 (note that a $25 kit does not include the lab test fee). They claim 99.9% accuracy.
A court-ordered paternity DNA test (or a “legal paternity test”) typically costs about $300 – $500, because they actually collect the specimens for the parents.

How long does a paternity test take?

Most of the time the lab will send the paternity test results back within 1-2 weeks.

Can I really lose my child if I’m the biological father?

Yes. But the sooner you act, the less likely that is to happen. In the first couple of years of a child’s life, such a result would be highly unusual. However, if a biological father has had no contact with a child for 12 years, then wants to be a parent, the court may easily find that it is not in the child’s best interests for him to be the legal father.

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