Stephen Miller: "We have communities all across this nation that 20 years ago, before the era of open borders, were completely peaceful, completely stable. Look at a place like Minneapolis. Post mass migration they're unsafe, they're violent, you cannot use the public parks."

The claim by Stephen Miller can be broken down into several components: 1) That 20 years ago, before an 'era of open borders,' communities like Minneapolis were completely peaceful and stable; 2) That since mass migration, these communities have become unsafe and violent; and 3) That public parks in Minneapolis are now unusable due to this violence.

First, the notion of an 'era of open borders' in the United States is misleading. The U.S. Has never had completely open borders in recent history; immigration policies have been regulated and enforced continuously. There is no clear policy shift around 20 years ago that would constitute a new 'era' of open borders.

Second, regarding Minneapolis's safety and stability two decades ago compared to now, crime data from official sources such as the Minneapolis Police Department and FBI Uniform Crime Reports show fluctuations in crime rates over time but do not support a narrative of complete peace followed by sudden violent deterioration solely attributable to immigration. Crime trends are influenced by multiple factors including economic conditions, policing policies, social dynamics, and more. While some neighborhoods in Minneapolis have experienced increases in crime or social challenges, attributing this directly to 'mass migration' oversimplifies complex urban issues.

Third, the claim that public parks in Minneapolis are unusable due to violence is an exaggeration. While there have been incidents of crime in public spaces, city officials and community organizations continue to maintain and promote park use. There is no credible evidence that public parks are broadly unsafe or closed off for use by residents.

The search results provided do not contain direct evidence supporting Miller's specific claims about Minneapolis or the impact of immigration on community safety or park usability. Instead, they focus on biographical information about Stephen Miller or unrelated topics. Independent crime statistics and urban studies research contradict the simplistic causal link implied by Miller.

In summary, while some communities face challenges related to crime and social change, the claim that Minneapolis was once completely peaceful before mass migration and is now unsafe with unusable parks is mostly false due to lack of supporting evidence and oversimplification of complex issues.