A row of split level houses and trees on a residential street
Defendant convicted of blowing up ex-girlfriend’s house is unable to prove expert testimony would change outcome of trial

Many gas fires and explosions are caused by a human mistake that results in a gas leak. Some fires and explosions cannot be attributed to a mistake by anyone and are just the result of an unfortunate set of circumstances. But occasionally, a gas explosion is the result of an intentional act, often an attempt to collect insurance money (see, for example, the December 2020 and January 2021 issues of BPN).

In January 2023, the Wisconsin Court of Appeals affirmed the conviction of a man who intentionally caused a gas explosion that destroyed his ex-girlfriend’s house. The motive was love, not money. The case is State v. Lillge.

Stormy Relationship

Craig Lillge and his girlfriend, who is referred to as A.B. in the court decision, had a stormy, on-again, off-again relationship. Lillge was a jealous individual who would react angrily — and sometimes violently — when he perceived that A.B. was flirting with other men. On multiple occasions, he let the air out of the tires on her car. He would frequently throw A.B.’s clothes and other possessions out into the front yard of the house she rented in Watertown, Wisconsin.


Enough was finally enough, and in November 2014, A.B. ended the relationship for good. She asked Lillge to return the key to her Watertown house. Suspiciously, he gave her a key that was a different color than the one she had given him in happier times. She questioned this, and he responded, “I don’t need a key to get into your house anyway, so it doesn’t really matter if I possess a key.” (Investigators later discovered that Lillge had several “bump keys” of the type typically used by locksmiths to gain access when the cut key for a lock is not available.)

Out for the Evening

On Dec. 20, Lillge called A.B.’s daughter and asked where she, her brother and A.B. would be that day. The daughter said that she and her brother would be staying overnight at a friend’s house, and that A.B. was “going out” for the evening. (Lillge apparently believed that A.B. would be staying overnight at a new boyfriend’s house, and in fact she did not return to the Watertown house that evening.) A.B.’s children were in the house alone until about 8:30 p.m., when they were picked up and taken to the friend’s house for the overnight stay. While at the house, they did go into the basement and did not smell gas.

At about 6 p.m. on Dec. 20, Lillge’s friend Hall came over to his house, and the two started drinking. Somewhere between 7:30 and 9:30 p.m., Hall left the house temporarily to pick up another friend. Around 9:30 p.m., Hall returned with the friend, and all three headed for a series of bars in Watertown to continue drinking. Meanwhile, at about 10:30 p.m., a neighbor of A.B.’s drove past her house and noticed clothing in the roadway. She drove around it and headed home.

Gaps in the Alibi

At about 2:30 a.m., Lillge and Hall left one of the bars and separated. The court decision is unclear as to where either of them went, but they got back together about 60 to 90 minutes later at a mutual friend’s house. From there, they proceeded to Lillge’s house, where they continued drinking until about 5 a.m., when Hall passed out and Lillge went upstairs. A little before 4 a.m., Lillge sent multiple accusatory texts to A.B. complaining about the end of their relationship and the new boyfriend. At 7:45 a.m., an explosion destroyed A.B.’s house. Fortunately, no one was in the house at the time.


Joshua Pudlowski, a special agent in the Wisconsin Department of Justice’s Division of Criminal Investigation, investigated the incident scene. He quickly confirmed that there had been an explosion and concluded that its origin was in the basement. He examined the gas appliances in the basement and found that they were not the source of leaking gas. He then found a gas line that had an open end with no cap. This apparently had been used to power a gas dryer that was no longer connected. At the end of the gas line, just upstream of the open end, was a valve that was in the fully open position. This, in his opinion, was the source of the gas for the explosion.

Pudlowski also noted evidence that the basement door was closed and locked at the time of the explosion. This would have prevented the escape of the lighter-than-air natural gas from the basement, allowing it to collect and find an ignition source, such as a pilot light. He found no evidence that the valve was accidentally turned to the open position and concluded that the valve must have been intentionally opened during the evening of Dec. 20 or the early morning hours of Dec. 21. A.B.’s children were in the basement before 8:30 p.m. on Dec. 20 and did not smell gas. The explosion was, in his view, the result of an intentional act by someone.

Finally, Pudlowski concluded that A.B.’s clothing had not been blown out of the house by the explosion and must have been put there sometime during the night before the incident.

Burglary & Arson

Even though there was no direct evidence that Lillge had entered the house and turned the valve to the open position, he was charged with burglary and arson. There was plenty of circumstantial evidence. Lillge had access to the house and bragged that he could enter it at any time. He had previously entered the house and thrown A.B.’s clothes and other possessions out into the street. His alibi witness, Hall, could not account for several key time periods during the night before the explosion.

Lillge waived his right to a jury, and the case was tried before a judge. After hearing all the evidence, the judge concluded that Lillge was guilty of burglary and arson. After the verdict, Lillge filed a motion for a new trial, arguing that his defense counsel was ineffective. Specifically, he said that his lawyer should have hired a fire investigation expert to counter the opinions of prosecution expert Pudlowski. He presented testimony from certified fire investigator John Agosti to support his motion. The trial court denied the motion and Lillge appealed.

The appellate court noted that in order to get a new trial, Lillge would have to show two things: First, that the defense counsel’s performance was deficient, and second, that Lillge’s defense was prejudiced by the deficient performance. In order to show prejudice, Lillge would have to demonstrate that there was a “reasonable probability” that if defense expert testimony had been presented, the result of the trial would have been different.

The court did not address the first issue, because on the second issue it found that there was not a reasonable probability that the result of the trial would have been different if defense expert testimony had been presented. Lillge’s post-trial expert Agosti agreed that the cause of the explosion was the ignition of a gas leak. In addition, Agosti could not rule out that the source of the gas leak was the open line and that someone intentionally opened the valve to cause the leak. He simply concluded there were other potential causes of a gas leak in the basement. However, he could not identify any specific other potential causes.

While the court recognized that Agosti’s testimony, if presented at a new trial, “could make a conceivable difference,” it would not make a “substantial difference.” There was not a reasonable probability that Agosti’s testimony, if presented at a new trial, would change the result. The court stated the following:

“We reach this conclusion in light of two factors, taken together: the limited nature of Agosti’s testimony and the strength of the evidence pointing to Lillge having entered A.B.’s house without her consent, opened the valve on the uncapped line, and closed the door to the basement.”

The court affirmed Lillge’s conviction and the trial court’s order denying him a new trial.

David Schlee is of counsel to The McCarthy Law Firm P.C. He may be reached at david@mokpclaw.com.


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