(CNN) President Donald Trump this week criticized Democratic presidential candidate Joe Biden for his role in passing "tough on crime" measures in the 1990s, but Trump once expressed support for some of the same policies Biden championed in the US Senate and even warned that dangerous "wolf packs" of young criminals would increase crime rates.

Trump's criticisms of Biden are undercut by positions he took in his 2000 book "The America We Deserve." Trump wrote in the book that he supported tougher sentencing and street policing and warned of "wolf packs" of young criminals roaming the streets, citing since-discredited statistical analysis that was linked to the "super predator" crime theory.

In a pair of tweets sent on Monday during his trip to Japan, the President wrote , "Anyone associated with the 1994 Crime Bill will not have a chance of being elected." He added , "....Super Predator was the term associated with the 1994 Crime Bill that Sleepy Joe Biden was so heavily involved in passing. That was a dark period in American History, but has Sleepy Joe apologized? No!"

Trump picked up on a line of criticism against Biden, including from some of his Democratic rivals, for his role in both crafting and shepherding the Violent Crime Control and Law Enforcement Act in 1994. The bill strengthened law enforcement across the country, provided federal money for new police and prisons, and tightened federal sentencing guidelines. Critics of the law, which was widely supported by Democrats at the time, contend it contributed to the era of mass incarceration that disproportionately impacts the African-American community.

Trump did not specifically address the crime bill in his book, but his positions in the book echo the much of the rhetoric in support of the bill at the time it was passed.

"President Trump never supported the disastrous 1994 crime bill, which disproportionately incarcerated black Americans, nor did he ever use the term 'super predators.' Actions and facts tell the story," Trump campaign spokeswoman Kayleigh McEnany said. McEnany also pointed to Trump signing major bipartisan criminal justice legislation that eased some mandatory minimum sentences and gave judges more leeway in sentencing.

Years before he turned his focus to Biden, Trump during the 2016 presidential campaign attacked Democratic nominee Hillary Clinton over her past use of the term "super predators" to describe young gang members who were thought to have no conscience or empathy. The term refers to a long discarded crime theory that predicted a spike in violent youth in the new millennium leading to increases in crime.

Trump did not use the term "super predator" in his book, but the statistics and claims made by Trump are linked to the theory and former academic proponents of it.

Wilson wrote that Americans "rightfully" believe "the prospect of innocent people being gunned down at random, without warning and almost without motive, by youngsters who afterward show us the blank, unremorseful faces of seemingly feral, pre-social beings." He predicted by the year 2000, "there will be a million more people between the ages of 14 and 17 than there are now" adding that "six percent of them will become high rate, repeat offenders — thirty thousand more young muggers, killers and thieves than we have now."

Trump backed the theory in his book, claiming crime from adolescents would spike in the 2000s.

"Most serious crime experts believe rates will skyrocket early in 2000 because there will be more adolescent boys around, and adolescent boys are especially dangerous," Trump wrote. "A lot of these boys don't have fathers. All they've got is a mother and that mother might well be a teenager herself. As anybody knows, a single mother is going to have a hard time controlling a normal boy, especially when he hits strutting age."

Trump continued, where he warned of the roaming "wolf packs" of adolescents that would create havoc.

"A government study of crime in America warns that when the population of adolescent males rises early next century, we're going to have wolf packs roaming the streets, and not only downtown. If these kids are anything like those who terrorized urban America in recent years, we're in for a very bad time," Trump added.

Earlier in his chapter on crime, Trump also backed other tough on crime measures in the 1990s writing, "If you're not tough on crime, then you're an enemy of the American Dream." Citing the theories of a coming crime spike, Trump argued for putting more people in prison.

"No, the problem isn't that we have too many people locked up. It's that we don't have enough criminals locked up," Trump wrote.

Trump also referenced his support for capital punishment in the book, specifically citing the case of the "Central Park Five." The case involved five teenage boys of color who were wrongly accused and convicted of beating and raping a woman in Central Park. Trump bought full-page ads that ran in several New York City newspapers that read, "Bring Back The Death Penalty. Bring Back Our Police!"

"Somehow, I began to hear about a great deal of sympathy for the young men. They had been so brutalized by the system, it was said, that they couldn't be held entirely responsible for the crime," Trump wrote. "I took a full-page ad in the New York Times to object and to state my belief that capital punishment would be the proper way to deal with the young men if the woman died. I was amazed by the number of politicians who called to express sympathy but who refused to take a similar position publicly. They were afraid of offending some of their constituents. That's the response from today's career politicians."

Trump also twice praised then-New York Mayor Rudy Giuliani's anti-crime policies in New York City. New York City under Giuliani embraced the "broken windows" theory of policing -- the idea that heavily enforcing punishments for small crimes like graffiti and vandalism would deter larger more serious crimes. Trump attacked those wanting softer sentences for those convicted of crimes.

"[U]nless we stand up for tough anti-crime policies, they will be replaced by policies that emphasize criminals' rights over those of ordinary citizens," Trump wrote. "Soft criminal sentences are based on the proposition that criminals are the victims of society. A lot of people in high places really do believe that criminals are victims. And they don't like the methods that have proved successful in crime control. As I write this book, there are protests here in my hometown against Mayor Giuliani's tough (and successful) anti-crime policies. I count some of my friends among the protesters. But they're singing a siren song."