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Legal Fatherhood (Paternity)

The information on this page is about proving or disproving that a male is the biological parent of a child.  

If you are in a same-sex relationship, you should talk to a lawyer if you have questions about whether you are a legal parent or want to become a legal parent. 

Note on language: This section uses the word “mother” to refer to a person who provides an egg, carries a child, and gives birth to a child. This section uses the word “father” to refer to a person who provides sperm to make a child. Although not all people identify with these terms, these words are used in the law, so we use them here for simplicity.  

  • Biological parent  A person who gives their genetic material (sperm or egg) to make a child. A biological parent is not always a legal parent.   
  • Legal parent A person that the government recognizes as a legal parent. There are special rules for when biological parents are automatically legal parents: 
    • Married parents: You’re automatically a legal parent to any children born to you or your spouse during a marriage or within 300 days after a divorce. Even if the child isn’t biologically yours.   
    • Unmarried mothers: You’re automatically a legal parent to any child you give birth to (unless you are a surrogate).  
    • Unmarried fathers: You’re only a legal parent if your name is on your child’s birth certificate, or you sign an official form saying you are the birth father.  
  • Parentage case, paternity case, filiation case – These are all names for legal cases in Oregon to figure out who the biological father is.      
  • Establishing paternity – This is the legal process of proving someone is a biological parent and making them a legal parent.  
  • Disestablishing paternity  – This is the legal process of making someone not a legal parent by proving they are not the biological parent to a child.   
  • CSP – Oregon Child Support Program. This is a government program that provides free help to parents with paternity and child support. The CSP can help you sort out paternity issues. It can also help you get child support from your child’s other legal parent.  
  • Legal custody – A decision from a court about who makes important decisions for a child, including health care, education, and religion. 

Maybe. If you want to get child support from the other parent or go to court to get legal custody and a visitation schedule for your child, your child must have a legal father first. Your child already has a legal father if your child’s father:  

  • Is listed on your child’s birth certificate; or 
  • Signed an official form, called a "Voluntary Acknowledgement of Paternity Affidavit," saying they are the legal father. 

You can ask the CSP to prove that person is your child’s biological father. This is called establishing paternity. You can ask to establish paternity any time before your child turns 18.  

To ask the CSP for help establishing paternity, you need to apply for CSP services.   

The CSP can help you establish paternity even if you don’t want child support from the other parent. 

Don’t write in anyone’s name on your child’s birth certificate or sign a form called a "Voluntary Acknowledgement of Paternity Affidavit." If you already did one of these things, you need to act quickly to make changes. In most cases, you only have one year to change your child's legal father. If it’s been more than one year, talk to an attorney. This is complicated.  

The CSP can help you sort out paternity issues for free. To get help from the CSP, you will need to apply for services. Visit the CSP website for information on applying.  

The CSP can help you figure out paternity issues even if you don’t want child support from the other parent. 

When parents are not married, a biological father can become the legal father by signing an official government form, called a Voluntary Acknowledgment of Paternity Affidavit.  

A father can sign this form at the hospital, or they can sign it after their child leaves the hospital. It is free to sign this form at the hospital or within 14 days of leaving the hospital.  

After 14 days (or if the child was born outside of a hospital), there is a small fee to complete this form and it must be signed in front of a notary public.  

If you need to sign the form after your child has left the hospital, or your child was not born at a hospital, ask one of these people or agencies for the form:  

You can ask for an official copy of the birth certificate from Oregon Vital Records. Only a parent on the birth certificate can get a copy. If you are not on the birth certificate as the legal father, Oregon Vital Records will reject your request. 

You can ask the CSP to help you become a legal parent. This is called establishing paternity.  

To ask the CSP for help establishing paternity, you need to apply for services with the CSP. You can find information about how to apply on the CSP website.  

The CSP can help you establish paternity even if you don’t want to start a child support case.  

If your wife has a child that is not biologically yours, you are still the legal parent of that child if the child was:  

  • Born while you are still legally married; or  
  • Born within 300 days after you are legally divorced.  

For example, if you’ve been separated from your spouse for five years, and your spouse has a child with a new partner, you are that child’s legal parent because you are still married. 

If you believe you are not the biological parent of your spouse's child, there is a process to disestablish paternity and be removed as the legal parent. You can ask the CSP for help with this.  

CSP may not help you disestablish paternity if your spouse doesn’t agree with this change. If this happens, talk to a lawyer.  

This process is complicated. You should act quickly if you need to change your child’s legal father. In most cases you only have one year to change your child’s legal father. The CSP can provide free help so you can sort out paternity issues. Visit the CSP website for more information.  

Only if the other parent lets you. The other parent has the power to say yes or no. If you want the legal right to spend time with your child, you must become the legal father.  

Only legal parents have these basic rights:   

  • The right to see their kids,
  • The right to raise their kids how they think is best,
  • The right to make medical, educational, and other important decisions,
  • The right to choose where their kids live,
  • The right to get government identification for their kids, and
  • The right to make financial decisions for their kids.

For more information on the rights of legal parents and parents with legal custody, go here.

No. If you do not want to use the free help of the CSP, you can also become a legal parent through a court case. But you will need to speak to a lawyer about filing this type of case. Oregon courts do not have free forms you can use for this. It is usually easier to use the free services of the CSP.  

No. You must do an official DNA test through the CSP or through an Oregon court case.   

If you get TANF (Temporary Assistance for Needy Families) cash assistance, the CSP will automatically start a paternity case (if your child doesn’t have a legal father yet) and a child support case.   

If CSP gets child support from the father, and the child support payment is higher than your TANF payment, you’ll get some additional money each month.  

If the CSP starts a paternity or child support case, but it's not safe for the other parent to have information about you, you have two options:   

  1. Ask the CSP to keep your contact information confidential. CSP documents usually include both parents' contact information. If it is not safe for the other parent to have your contact information, submit a Claim of Risk form to keep your personal information protected while the child support case moves forward. Ask your child support caseworker for this form.  
  2. Ask the CSP to stop the case. If you are in danger and you do not want the CSP to contact the other parent at all, submit a Good Cause form. This form allows you to ask the CSP not to establish paternity or try to get child support. Ask your child support caseworker for this form. 

For more information on keeping your information safe during a paternity or child support case, visit the CSP website

No. The CSP does not help with custody. You must turn in papers with the court to get those orders. For more information on custody cases, go here

Yes. If the CSP establishes paternity, they can also help you get child support from your child’s legal father. This is optional. You can also request that the CSP only establish paternity, and not go after the father for child support.  

For more on child support go here.  

No. There is no cost. DNA testing done through the CSP is also free. Learn more about free paternity services and testing on the CSP website

Read the papers carefully. They will tell you how much time you have to disagree. They will also tell you how to tell CSP that you disagree.  

After getting the paperwork, you have two options:  

  1. If both parents agree on the child’s father: both parents can sign a "Voluntary Acknowledgment of Paternity Affidavit." If you choose this option, the CSP will not do DNA testing to prove paternity.  
  2. If you disagree on who is the child’s father: you can ask for DNA testing through CSP. Be sure to go to the DNA appointment on time. If the mother started the case, you may automatically become the legal father if you miss the appointment. 

Read the paperwork carefully. If you disagree that you are the legal father or disagree with the amount of child support, you must notify the CSP. But you need to act quickly.  You only have a short time to act.  

The paperwork will tell you how to tell the CSP you disagree, and the deadline to act.  

In most situations, you can’t avoid paying child support, you can only disagree with the amount. But you don’t have to pay child support if you are getting disability benefits, TANF benefits, or are in jail or prison.       

If you disagree with the amount of child support listed in the CSP paperwork, or have a good reason not to pay support, you need to tell the CSP quickly. You only have a short time to act.  

The CSP paperwork will tell you how to disagree and how much time you have. For more information on child support, go here

Either parent can try cancel their Voluntary "Acknowledgement of Paternity Affidavit," but only in certain situations.  

  1. If it has been less than 60 days since you signed the form, you can call the Center for Health Statistics at 971-673-1147 or email them at CHS.Amendments@oha.oregon.gov and ask for the "Rescind of Voluntary Acknowledgment" form for either the mother or the father. There is no fee for filing this form.  
  2. If it has been less than one year since you signed the form, you can tell the CSP that you want to do DNA testing. Contact the CSP for help.   

If you get paperwork about paternity or child support and do nothing, here’s what will most likely happen:  

  1. You will become the child’s legal father; and 
  2. You will have to pay child support to the other parent if they asked for child support.   

No. But they do get the same rights as the other legal parent. For more information about the rights of parents and legal custody, go here

A court or the CSP cannot make that decision without notifying you of the case and giving you a chance to disagree. If you learn you are the legal parent and you never received notice of the process, then there may be ways to challenge it. You should contact the CSP or get legal help right away.  

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