President Donald Trump’s sacking of Attorney General Jeff Sessions has raised concerns among those who wish to see the investigation by special counsel Robert Mueller continue unimpeded.

Those same people will likely not lament Session’s ouster based on what he accomplished as attorney general. In my view, his tenure as attorney general saw him on the wrong side of most important law enforcement decisions. On the other hand, many will point to him as a historic champion for “law and order” conservatism at the highest level.

Here are three areas where Sessions will most be remembered.

1. Controversial from the start

Sessions’ tenure began back in early 2017. During his confirmation hearings, Sessions testified incorrectly under oath that he had had no contacts with Russian officials during his active role in the 2016 Trump campaign. When it became public that he had met with the Russian ambassador, he claimed he had not lied. But because of those contacts and his role in the campaign, he recused himself from the Russia investigation.

This caused a rift between him and President Trump, which was ironic, given that Sessions enthusiastically implemented most of Trump’s policy priorities. In the end, the perceived lack of personal loyalty from the recusal – the necessity of which seemed pretty straightforward to most outside legal observers – proved to be Sessions’ downfall.

2. Crackdown on drugs

Sessions enthusiastically waged the war on drugs, much to the chagrin of those who considered that war a proven failure.

Sessions instructed prosecutors to seek the maximum possible sentences for drug offenses and in 2017 reversed an Obama-era Department of Justice policy that barred the Department of Justice from contracting with private prisons.

He also reversed the Obama-era policy against federal enforcement of marijuana possession laws in states where marijuana had been decriminalized. This meant low-level drug offenders were subjected to serious federal criminal penalties for dealing a substance made legal under state law. This position highlighted a tension between the dueling conservative principles of being “tough on crime” while also respecting states’ rights.

Sessions’ criminal justice policies would put many more people in jail, exacerbating the perceived problem of mass incarceration. America is responsible for 25 percent of the world’s imprisoned persons despite having only 5 percent of the world’s population. As attorney general, Sessions embraced the policies seen by many as major causes of this problem, including harsh mandatory minimum sentences; the use of private prisons which create a for-profit incentive to incarcerate; and imprisoning persons who commit low-level, nonviolent drug offenses.

Sessions and his supporters argued that illegal drugs are a scourge, and that swift and certain punishment was the best means of combating it. This included a Sessions-led crackdown on doctors, drug dealers and traffickers whose distribution of drugs through either legal or illegal means fed the nation’s opioid epidemic, one of the signal Sessions efforts which garnered the most bipartisan support.

3. ‘Zero tolerance’ at the border

On immigration, Sessions faithfully put into action the tough talk of the president – even where, some would say, supporting evidence was lacking.

Research shows that immigrants commit fewer crimes in the U.S. than non-immigrants.

But Sessions often falsely claimed that there was a strong correlation between immigration – including legal immigration – and crime, including terrorism. He pointed out that members of the notorious MS-13 gang came to the U.S. from other countries – although, ironically, the gang got its start here in the U.S.

Sessions used the false connection between immigrants and crime for sharp reductions in the number of Syrian refugees the U.S. should admit, despite the fact that it is IS terrorists that they themselves are fleeing. He also used it to justify a crusade against so-called “sanctuary cities,” cities which forbade local law enforcement officials from enforcing certain federal immigration laws.

As sanctuary city advocates observe, such enforcement might make local immigrant communities less likely to report crimes, serve as witnesses, and otherwise cooperate with local law enforcement to reduce ordinary crime. Sessions’ January 2017 executive order to suspend all federal funding to such cities was eventually blocked by the courts as unconstitutional overreach.

But the most prominent and devastating aspect of his immigration policy was creating a “zero tolerance” policy at the border – the idea that every undocumented person coming to the border without documentation would be detained and criminally prosecuted, even those pursuing valid and legal asylum claims.

The policy triggered the widely criticized practice of family separation, in which federal agents separated thousands of children from their parents. Parents accused of no crime went months without seeing their young children, talking to them or even knowing where they were. The trauma produced lasting effects on many of the younger, more vulnerable children. Many remain separated.

At the same time, the get-tough-on-immigration approach shared by Sessions and Trump resonated with many Americans, especially Republicans. Trump leaned on it heavily to mobilize his base in the run-up to the midterm elections.

Sessions effectively pursued the conservative goals he had long championed and which his boss favored.

Steven Mulroy does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.