DeYoung was born September 12, 1874, in Chicago, Illinois, to parents that had both immigrated as children to the United States from The Netherlands.

However, when he was five years of age, DeYoung's family moved to the village of Roseland, Illinois, which was ethnically Dutch at the time.

Several years later, his family moved to South Holland, Illinois, which was a main center of Chicago area's Dutch population.

[2] DeYoung was educated until leaving school at the age of twelve when his family returned to the West Side of Chicago in 1887.

He left this job to enroll at Bryant & Stratton Business College, but stopped attending after health issues prevented him from doing so.

[2] Instead of seeking reelection to the state house, he opted to run for a judgeship on the Cook County Probate Court.

[2] In June, DeYoung was an unsuccessful candidate for election to a full term on the Circuit Court of Cook County.

The Chicago Tribune hailed the decision as being, "the biggest step forward in criminal procedure in the last fifty years".

[2] In People v. Fisher, DeYoung's majority decision ruled that, in a felony trail where the plea is not guilty, the defendant can waive a jury trial and have their cause heard and determined by the judge.

It would be quoted in length in the landmark United States Supreme Court decision Village of Euclid v. Ambler Realty Co., which upheld the national constitutionally of land use zoning.

[2][8][9][10] Serving as honorary pallbearers at his funeral were his fellow Illinois Supreme Court justices and former governors Edward Fitzsimmons Dunne, Charles S. Deneen, and Frank Lowden.