The "Last Week Tonight" host called out "deeply irresponsible" police departments.
Fentanyl is 50 times as strong as heroin and 100 times as strong as morphine, according to the CDC.
Williams, 54, died of acute drug intoxication Sept. 6.
The child is believed to have brought nearly 40 bags of the deadly drug into his Hartford school, leading to his overdose in the gymnasium.
Overdose deaths have been rising for more than two decades, accelerated in the past two years and jumped nearly 30% in the latest year.
Miller’s assistant found the rapper unresponsive in his Los Angeles home on Sept. 7, 2018, and he was declared dead soon after.
President Joe Biden's administration hopes concessions to progressives can help win over Congress on confronting the opioid epidemic.
GOP Rep. Andy Biggs seemed angry after the U.S. Border Patrol intercepted “fentanyl to kill 238 million Americans” at the southern border.
Rep. Andy Biggs of Arizona seemed angry that "enough fentanyl to kill 238 million Americans was seized at the southern border last month."
Congress and the Biden administration appear set to extend a Trump administration decision to impose harsher penalties on drug crimes.