The 15-minute observation rule for Michigan breath tests

Michigan's State Police rules allow an evidential breath test only after the person has been observed for at least 15 minutes by a certified operator, during which the person must not smoke, regurgitate or put anything in the mouth other than the test mouthpiece.^[1] A similar 15-minute rule applies to the roadside preliminary breath test.^[2] The current rule, last amended in 2023, says expressly that the operator need not stare continuously and that breaks of a few seconds do not void the observation.^[1] When the rule is not followed, courts have asked whether the violation was significant enough to call the result's accuracy into question.^[3]

What the rule says

The evidential-test rule is Mich Admin Code R 325.2655(e). It reads in part: "An individual shall be administered an evidential breath alcohol analysis on an evidential breath alcohol test instrument only after being observed for not less than 15 minutes before collection of the breath sample by at least 1 appropriate class operator that is certified in accordance with R 325.2658. The observation period may be conducted by more than 1 operator working in concert."^[1]

The same rule spells out what the observation does and does not require:^[1]

• The operator "need not stare continuously" at the person, but must be close enough to be aware of the person's actions and conditions.^[1]
• The operator may do paperwork or data entry while the person is in view.^[1]
• "Breaks in the observation period lasting only a few seconds do not invalidate the observation if the operator can reasonably determine that the individual did not smoke, regurgitate, or place anything in his or her mouth during the breaks."^[1]

The observing operator must be certified. A Class III operator is the class certified to run a subject test on an evidential instrument.^[5] These rules were amended in 2023.^[6]

Why the rule exists

The rule itself lists what the observation guards against: smoking, regurgitating, and putting something in the mouth.^[1] The breath-sampling rule also tells the operator not to take the second confirming sample if something is found in the mouth that could interfere.^[7] The courts' language points the same way: in Robe the question was whether the violation called "into question the accuracy" of the test.^[3]

The PBT version of the rule

For the roadside PBT, R 325.2657a(1) says a PBT may be given only by a certified operator and only after the operator determines that the person "has not smoked, regurgitated, or placed anything in his or her mouth for not less than 15 minutes."^[2] The wording differs: the evidential rule speaks of the person being "observed," while the PBT rule speaks of the operator "determining."^[1][2] The Traffic Benchbook still quotes the PBT procedure under the older number R 325.2655(2).^[8]

What courts have done when the rule was not followed

Case	Facts	Result
People v Boughner (1995), evidential test	About 35 minutes on video, but the operator observed for no more than eight minutes, not continuously, and the defendant's hand was on his face or in his mouth during the taped time.[4]	The failure sufficiently undermined accuracy to warrant reversal of a plea-based conviction.[4]
People v Wujkowski (1998), evidential test	The operator observed for more than 15 minutes, then walked away for six seconds to check the machine while another officer was present.[4]	A de minimis, technical violation; no suppression.[4]
People v Robe (2021), PBT	The officer observed for about three minutes, with no evidence anyone else observed for the remaining 12.[3]	The violation was significant and called accuracy into question; the PBT had to be excluded from the probable-cause analysis.[3]
People v Robe (2022, unpublished), on remand	The question was whether the blood-draw warrant stood without the PBT.[9]	The court held the warrant lacked probable cause without the PBT and remanded on the good-faith exception.[9]

Robe used the evidential-test cases because "the administrative rule governing Breathalyzer tests is similar to the one controlling the administration of PBTs."^[3] Boughner and Wujkowski applied earlier versions of the rule; the current version, amended in 2023, expressly tolerates breaks of a few seconds.^[4][1]

A related point came up in People v Mullen: a blood-warrant affidavit omitted that the driver had paper in his mouth a few minutes before the PBT, but the Court of Appeals held a magistrate could still find probable cause given nothing that significantly undercut the 0.15 result and other evidence of intoxication.^[10]

What the rule does not mean

"Any interruption voids the test." The current rule says brief breaks of a few seconds do not invalidate the observation if the operator can reasonably determine nothing went into the mouth, and Wujkowski found a six-second break de minimis.^[1][4]

"Fifteen minutes in the patrol car counts automatically." The rule requires observation by a certified operator, or operators working together, close enough to be aware of the person's actions.^[1] Whether time spent elsewhere meets that standard depends on the facts, and practice varies by court.

"A violation means the case is dismissed." The reported remedies are exclusion of the result, or reversal where the result was the basis of a conviction; none of the cases above ordered dismissal because of the rule alone.^[3][4]

How the issue reaches a court

An observation-period problem can come up in a motion to suppress the result, in a challenge to probable cause for the arrest or a warrant, or at trial.^[3][9] At trial, jurors are told to consider whether the test was given correctly and whether the person giving it was properly trained.^[11] On request, the prosecutor must provide police reports and the defendant's recorded statements, including electronic recordings, and body-camera footage must be kept while a prosecution is pending.^[12][13] See motions to suppress evidence, discovery and video evidence, and how breath test results are challenged.

For anyone reviewing a test, the observation start and end times, the operator's name and the instrument location may appear in the test records and reports. Booking-room or body-camera video, where it exists, can show who was present and for how long. Writing down what you remember about the time at the station soon after the arrest helps keep the details straight. The station-test procedure as a whole is described on the station breath test.