MICHAEL J. KELLY, J.

Defendant Bette Huster appeals by leave granted an order of the circuit court denying her motion for a rehearing of her motion for summary disposition under MCR 2.116(C)(7). The circuit court ruled that defendant was not immune from liability for her actions as guardian ad litem for plaintiff Renee Bullock in an underlying child custody suit between Ronald Bullock, plaintiff's father, and Sharon Pope, her mother. We affirm.

I

Plaintiff Renee Bullock was born in May 1983. In March 1985, Ronald Bullock and Sharon Pope separated, and a bitter child custody battle over plaintiff ensued. Initially, Bullock was given custody of plaintiff. In April 1988, defendant Bette Huster accepted appointment as guardian ad litem for plaintiff. Pope subsequently alleged that Bullock had sexually abused plaintiff. In December 1988, Pope was awarded custody of plaintiff and began denying Bullock visitation. After being found in contempt of court, Pope fled to Georgia with plaintiff, which led to a conviction of parental kidnapping and a sentence of ninety days' imprisonment and community service. Despite Pope's actions, defendant continued to recommend that Pope retain custody. Apparently, defendant conducted little investigation into the allegations of sexual abuse against Bullock and displayed hostility toward him and those who rendered expert opinions in his favor.

In December 1992, plaintiff filed the instant lawsuit, alleging that defendant acted in a negligent and grossly negligent manner while performing her duties as guardian ad litem, that she breached an express or implied contract with plaintiff and implied warranties incident to that contract, and that she intentionally inflicted emotional distress upon plaintiff. Plaintiff also claimed that defendant failed to conduct sufficient investigation and cited numerous instances when defendant was negligent or intentionally deceitful in her analysis of plaintiff's expert opinions. Bullock was appointed next friend under MCR 2.201(E)(1) (b).

Bullock had moved for the removal of defendant as guardian ad litem in the underlying action. This motion was denied in February 1993 on the basis of insufficient evidence. That same month, defendant moved for summary disposition in the instant action on the basis that she was immune from liability as guardian ad litem and that plaintiff was collaterally estopped from relitigating the issue of defendant's negligence in view of the determinations made in the underlying action. In April 1993, the circuit court denied the motion. Defendant filed a motion for reconsideration and for a stay of proceedings pending appeal. In May 1993, the circuit court denied these motions. In August 1993, this Court granted defendant's application for leave to appeal.

II

Defendant first argues that she is entitled to immunity as guardian ad litem. We disagree.

At issue is the scope of the governmental immunity act of 1986, MCL 691.1407; MSA 3.996(107). Just before the act was proposed, the Supreme Court decided nine consolidated governmental immunity cases, commonly referred to as Ross v Consumers Power Co, 420 Mich. 567; 363 N.W.2d 641 (1984). The response of the Legislature was swift and comprehensive. The Legislature took an immunity provision that previously had applied only to governmental agencies (subsection 1 of MCL 691.1407; MSA 3.996[107]) and added several other provisions defining the extent of immunity available to officers, employees, members, and volunteers of government agencies (subsections 2 and 3), public hospitals and medical care facilities (subsection 4), and judges, legislators, and the elective or highest appointive executive officials of all levels of government (subsection 5). See House Legislative Analysis, HB 5163, January 16, 1986. This was all accomplished in conjunction with the extensive tort reform act of 1986, 1986 PA 175. While the Legislature left intact a provision in subsection 1 that affirmed common-law rules regarding the immunity of government agencies as the rules existed before July 1, 1965 (the effective date of the original governmental immunity act), the Legislature did not provide for the preservation of any common-law rules with respect to the government officials covered in the other subsections of the 1986 act.

Clearly, the 1986 act represents a comprehensive review of governmental immunity. Yet, the Legislature failed to include guardians ad litem within the class of persons entitled to immunity. Where the Legislature undertakes such broad reform, the expression of one thing in the resulting statute may be deemed the exclusion of another. See Jennings v Southwood, 446 Mich. 125, 142; 521 N.W.2d 230 (1994). While subsection 5 grants immunity to "judges," there is no indication that this term should be construed beyond its plain meaning to include persons appointed by judges in any capacity. The Legislature drafted subsection 5 to apply only to those persons who are the ultimate decision makers in their respective branches of government — for example, "legislators" and "elective or highest appointive executive officials." Subsections 2 and 3, regarding employees of government agencies, are inapplicable to guardians ad litem. No other provisions in the act apply to guardians ad litem. Under these circumstances, we hold that the intent of the Legislature was to exclude guardians ad litem from the scope of governmental immunity. The wisdom of this exclusion is not a matter for our review. Id., citing City of Lansing v Lansing Twp, 356 Mich. 641, 648; 97 N.W.2d 804 (1959). The circuit court's denial of defendant's motion for summary disposition on immunity grounds was proper.

III

Defendant also asserts that plaintiff is collaterally estopped from relitigating the propriety of the circuit court orders in the underlying child custody case.

Collateral estoppel precludes relitigation of an issue in a subsequent, different cause of action between the same parties when the prior proceeding culminated in a valid final judgment and the issue was actually and necessarily determined in the prior proceeding. Schlumm v Terrence P O'Hagan, PC, 173 Mich. App. 345, 354; 433 N.W.2d 839 (1988). The ultimate issue in the second action must be the same as that in the first. Detroit v Qualls, 434 Mich. 340, 357; 454 N.W.2d 374 (1990). The issue must have been necessarily determined — that is, essential to the resulting judgment — in the first action. Id. It also must have been actually litigated — that is, put into issue by the pleadings, submitted to the trier of fact, and determined by the trier of fact. VanDeventer v Michigan Nat'l Bank, 172 Mich. App. 456, 463; 432 N.W.2d 338 (1988). The parties must have had a full and fair opportunity to litigate the issue in the first action. Kowatch v Kowatch, 179 Mich. App. 163, 168; 445 N.W.2d 808 (1989).

The ultimate issue in the custody action was whether plaintiff's best interests would be served under Bullock's care or by remaining with Pope. The ultimate issue in this case is defendant's negligence or misconduct as guardian ad litem. The issue of defendant's negligence was not essential to the custody decision. The circuit court's denial of defendant's motion for summary disposition on collateral estoppel grounds was proper.

Affirmed.

E.R. POST, J., concurred.