When law enforcement officers stop and question people for no particular reason, or in the case of the Drug Enforcement Administration, based on a vague perception that a person exhibits "characteristics indicative of drug trafficking," is it any wonder that allegations of racial profiling result?

A recent report from the Justice Department Inspector General is a case study in the dangers of this kind of unfettered, unmonitored law enforcement conduct. It examines the DEA's use of so-called "cold consent" encounters with members of the public – instances in which officers stop individuals and seek to question, search, and possibly seize cash from them, ostensibly with their consent. The DEA uses such encounters to stop drug trafficking at transportation facilities. It considers the encounters "voluntary" because they're not based on any specific indication of criminal activity, and the officers therefore are not requiring anyone to stop and submit to a search.

There are two main problems with this approach.

The first is that, as the report notes, "cold consent encounters are more often associated with racial profiling than contacts based on previously acquired information." Meaning: When law enforcement officers don't have adequate reasons for searching people, they tend to search racial and ethnic minorities disproportionately. Recently revised guidance from the Department of Justice makes clear that racial and ethnic profiling is unfair, impermissible, and "simply not good law enforcement."

That's precisely what seems to have happened with the DEA's cold consent encounters. Separate allegations of profiling from two African-American women prompted the IG to conduct its investigation. DEA agents stopped and searched each of the women on a jetway while they were preparing to board a flight. The agents said the first complainant was "pacing nervously" and "exhibited other characteristics" that made them suspicious that she was engaged in drug trafficking.

When officers stop people based on such subjective, ambiguous grounds – basically, their gut – they inevitably allow their own biases to influence those decisions. Similar allegations of racial profiling have been leveled at the TSA for its use of "behavior detection officers" in airport screening areas.

More demographic information on cold consent encounters would help reveal how much of a role of racial profiling plays. Conveniently for the DEA, it doesn't collect or analyze such information. As the IG concluded, this failure to collect demographic data prevents anyone from assessing "whether the encounters are conducted in an unbiased or effective manner."

For the DEA, ignorance is innocence.

The second major problem with cold consent encounters is that they're often not actually consensual. The story of the second woman who complained to the IG is an example. DEA agents told her that they were conducting "secondary screening" – a non-voluntary procedure typically carried out by the TSA – of passengers prior to boarding. She reasonably assumed that she had no choice but to submit to the search.

The IG found that DEA agents had used similarly misleading techniques near TSA checkpoints at airports on other occasions, misrepresenting themselves as conducting "secondary inspection" that appeared to be anything but voluntary. DEA agents, the report finds, also failed to advise people that they could refuse to consent to searches, or to request that people read and sign a standard DEA consent form.

When consent is relied on to justify a search, it must be shown that there was a clear and unambiguous consent, freely and voluntarily given. Troublingly, there's reason to believe the DEA is not only searching people without adequate consent or reasons, but also engaging in unlawful profiling in the process.