Posted on June 4, 2020

What Is The Best Interest Of The Child In An Illinois Custody Case?

Illinois divorce and family judges decide almost everything related to the children in a divorce or parentage matter based on what is in the children’s best interests.  What exactly does “Best Interest Of The Child” mean in an Illinois divorce or custody case?

What The Illinois Statute Says About Best Interests Of The Child

The exact term “custody” no longer exists in Illinois, The Illinois statute dissected custody into two parts; decision-making and parenting time.  The Illinois statute declares best interests of the child as the standard for allocating both parenting time and parenting responsibilities.

“The court shall allocate decision-making responsibilities according to the child’s best interests” 750 ILCS 602.5(a)


“The court shall allocate parenting time according to the child’s best interests.” 750 ILCS 602.7(a)

The court then provides explicit standards for what the courts shall consider when deciding the children’s best interests.

“In determining the child’s best interests for purposes of allocating significant decision-making responsibilities, the court shall consider all relevant factors, including, without limitation, the following:” 750 ILCS 602.5(c)


“In determining the child’s best interests for purposes of allocating parenting time, the court shall consider all relevant factors, including, without limitation, the following:” 750 ILCS 602.7(b)

You’ll notice that while decision making and parenting time are supposed to be two separate items that are individually allocated to each parent…they are decided exactly the same way. So, while custody no longer exists on paper, it still exists in concept and if you treat the two twin ideas, parenting time and decision-making, as the same thing (custody) to your advantage, you will likely get more custody which means more parenting time and more decision making.

The factors that are considered in both parenting time and parenting decision-making are as follows

  • Wishes of the child. 750 ILCS 5/602.5(c)(1) and 750 ILCS 5/602.7(b)(2)
  • Child’s adjustment to his or her home. 750 ILCS 5/602.5(c)(2) and 750 ILCS 5/602.7(b)(6)
  • The mental and physical health of all individuals involved. 750 ILCS 5/602.5(c)(3) and 750 ILCS 5/602.7(b)(7)
  • Wishes of the parents. 750 ILCS 5/602.5(c)(7) and 750 ILCS 5/602.7(b)(1)
  • The child’s needs. 750 ILCS 5/602.5(c)(8) and 750 ILCS 5/602.7(b)(8)
  • The distance between the parents’ residences, the cost and difficulty of transporting the child, each parent’s and the child’s daily schedules, and the ability of the parents to cooperate in the arrangement. 750 ILCS 5/602.5(c)(9) and 750 ILCS 5/602.7(b)(9)
  • The willingness and ability of each parent to facilitate and encourage a close and continuing relationship between the other parent and the child. 750 ILCS 5/602.5(c)(11) and 750 ILCS 5/602.7(b)(13)
  • The physical violence or threat of physical violence by the child’s parent directed against the child or other member of the child’s household. 750 ILCS 5/602.5(c)(12) and 750 ILCS 5/602.7(b)(11)
  • The occurrence of abuse against the child or other member of the child’s household. 750 ILCS 5/602.5(c)(13) and750 ILCS 5/602.7(b)(14)
  • Whether one of the parents is a sex offender, and if so, the exact nature of the offense and what, if any, treatment in which the parent has successfully participated. 750 ILCS 5/602.5(c)(14) and 750 ILCS 5/602.7(b)(15)
  • Any other factor the court expressly finds to be relevant. 750 ILCS 5/602.5(c)(15) and 750 ILCS 5/602.7(b)(17)

Those are 11 identical factors that determine the best interests of the child for both allocating parenting time and parental decision-making.

You should be able to see that it is in the child’s best interests that either:

1) Both parents share decision-making and parenting time under appropriate circumstances


2) One parent controls all of the decision-making and all (or almost all) of the parenting time

The difference between the two options is ALL based on the best interests of the child.

How Do You Come To An Agreement On What The Best Interests Of The Child Are?

95% of all divorce and custody cases end up settling between the parties.  The parenting plan you can agree to, is always superior to the parenting plan according to the Illinois Marriage and Dissolution of Marriage Act. 

There are two avenues the parents can pursue in order to determine the best interests of the child in advance of going to court; 1) family therapy and 2) mediation.

Engaging in family therapy is a massive step for a couple that is separating.  But, if the couple can muster the maturity to discuss their separation in a safe environment that considers the emotions of the parties and the children first, it can be the best option. 

Honestly, I have rarely seen the option of preliminary family therapy invoked. It’s probably because the folks that are able to determine the best interests of the child via family therapy don’t hire family law lawyers. I presume they are able to resolve and finalize their issues without getting the courts involved at all.  This always works…until It doesn’t.

Alternatively, parents who can’t initially agree on what the bests interests of the children are must go to mandatory mediation. “The court shall order mediation to assist the parents in formulating or modifying a parenting plan or in implementing a parenting plan” 750 ILCS 602.10(c).

A mediator is supposed to help the two parties find common ground not decide something so fundamental as “what is the best interest of the child?” If both parents are truly committed to their child’s best interests, they may be able to codify how to act in those best interests with the help of a mediator.

How To Prove What Is In The Best Interests Of The Child In An Illinois Divorce Or Parentage Action?

In Illinois, If the parents disagree as to how the  decision-making or the parenting time will be allocated amongst themselves, the Illinois divorce court must step in and decide for them.

Determining something as broad as “the best interests of the child” is not something that a family law judge can do in 10 minutes while the family law judge handles his or her other 40 court calls that day.

“[A] best interests determination cannot be reduced to a simple bright-line test and…a ruling on the best interests of a child must be made on a case-by-case basis, depending, to a great extent, upon the circumstances of each case.” (Internal quotation marks omitted.) In re Marriage of Fatkin, 2019 IL 123602

So, an Illinois domestic relations court is empowered to appoint a Guardian Ad Litem to step in and represent the best interests of the child. A guardian ad litem is an attorney who has completed the appropriate training to investigate and make recommendations as to what is in a child’s best interests. Guardian Ad Litems are almost always practicing family law attorneys.

“In any proceedings involving the support, custody, visitation, allocation of parental responsibilities, education, parentage, property interest, or general welfare of a minor or dependent child, the court may, on its own motion or that of any party, appoint an attorney to serve in one of the following capacities to address the issues the court delineates” 750 ILCS 5/506.

The Guardian Ad Litem’s role is largely investigative. 

“The guardian ad litem shall investigate the facts of the case and interview the child and the parties.” 750 ILCS 5/506(a)(2)

Once the investigation is completed, the guardian ad litem issues a report of recommendations to the judge that would best serve the child’s best interests.

“The guardian ad litem shall testify or submit a written report to the court regarding his or her recommendations in accordance with the best interest of the child. The report shall be made available to all parties.” 750 ILCS 5/506(a)(2)

This report is the end-all-be-all to determine the child’s best interests.  The Illinois family law judge will almost always adopt the entirety of the report as it’s final order.

How To Argue For Or Against The Guardian Ad Litem’s Report In Determining The Best Interests Of The Child

Once the Guardian Ad Litem’s report is issued, a final hearing as to the child’s best interests may be scheduled.  At this hearing, you can make final arguments based on the report and even question the Guardian Ad Litem’s as to how they made their final recommendations.

“The guardian ad litem may be called as a witness for purposes of cross-examination regarding the guardian ad litem’s report or recommendations.” 750 ILCS 5/506(a)(2)

During your arguments for or against the Guardian Ad Litem’s report you can make the following statements:

“The child is young and should be with his or her mother”

Pros: This makes a lot of sense.  Especially, if the mother is breast-feeding. A new father may not know what he’s doing with the child.  Also, you can always change parenting time later when the child is older.

Cons: There is no presumption that one parent is superior to another parent purely because of the parent’s sex alone.  Pratt v. Pratt (1975), 29 Ill. App.3d 214

“One parent has no experience raising a child”

Pros: “[Tjhe physical and mental condition of both parents is necessarily a material issue in cases involving custody of a child.” Marcus v. Marcus, 24 Ill.App.3d 401, 406, 320 N.E.2d 581, 584 (1st Dist. 1974).

Cons: The inexperienced parent can rely on their family, cultural background and traditions in order to parent effectively. Anagnostopoulos v. Anagnostopoulos, 22 Ill.App.3d 479, 317 N.E.2d 681 (1st Dist. 1974)

“One parent is too strict”

Pros: Flexibility is the hallmark of a good parent. Rigidity doesn’t help the parent cooperate or adapt to the child’s environment. 

Cons: Strict discipline is a positive parenting feature. Wilner v. Wilner, 131 Ill.App.2d 891, 266 N.E.2d 918 (3d Dist. 1971).

Finally, there are subjects you cannot and should not bring up when arguing about the child’s best interests in court.

Past marital misconduct such as adultery, alcohol, drugs even violence, shall not be considered so long as it does not affect the child. Huey v. Huey, 25 Ill.App.3d 20, 322 N.E.2d 560 (5th Dist. 1975).

The relative wealth of the parents is also a taboo subject in custody proceedings. So, taboo, the last time wealth was brought up in a custody appeal was in 1930.  People v. Schaedel, 340 Ill. 560, 173 N.E. 172 (1930).

Despite Illinois’ law’s preference for a traditional lifestyle for a child, religion should not be heavily considered during a custody proceeding. Frank v. Frank, 26 Ill.App.2d 16, 167 N.E.2d 577 (1st Dist. 1960).

And, of course, the race of the parents has nothing to do with the best interests of the child. Fountaine v. Fountaine, 9 Ill.App.2d 482, 133 N.E.2d 532 (1st Dist. 1956)

Using Best Interests Analysis To Get Permission To See Your Child

After a terrible incident, courts can restrict one parents access to a child.

“After a hearing, if the court finds by a preponderance of the evidence that a parent engaged in any conduct that seriously endangered the child’s mental, moral, or physical health or that significantly impaired the child’s emotional development, the court shall enter orders as necessary to protect the child.” 750 ILCS 5/603.10(a)

This hurts the parent but it also hurts the child. A parent can regain access to their child by arguing that the child’s best interests creates a need for parenting time.

“The court may modify an order restricting parental responsibilities if, after a hearing, the court finds by a preponderance of the evidence that a modification is in the child’s best interests” 750 ILCS 5/603.10(b)

This underscores the principle that, when in doubt, argue about the child’s best interests as that factor should always come first in an Illinois family law court’s considerations.

If you’re worried about your child’s best interests and how to present them to a therapist, mediator, Guardian Ad Litem or Illinois family law judge, call my Chicago, Illinois family law office to schedule a free consultation with an experienced Illinois child custody lawyer.

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Russell Knight

Russell D. Knight has been practicing family law as a Chicago divorce lawyer since 2006. Russell D. Knight amicably resolves tough cases while remaining a strong advocate for his client’s interests.

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